A dimensionless water invasion map drawing method for fracture-cavity carbonate edge-water reservoirs

Abstract

The present invention discloses a dimensionless water invasion map drawing method for fracture-cavity carbonate edge-water reservoirs, including: obtaining basic parameters of matrix, fractures and caves, and basic reservoir parameters by collecting on-site reservoir and geological data; obtaining dimensionless water body radius; obtaining matrix-to-fracture crossflow coefficient, cave-to-fracture crossflow coefficient, matrix system elastic storage ratio, fracture system elastic storage ratio, and cave system elastic storage ratio; establishing a plane radial flow mathematical model for fracture-cavity triple medium edge-water reservoirs; and drawing a dimensionless water invasion map. The present invention draws the relationship curve between dimensionless water invasion and dimensionless time for infinite water body and closed water body plane radial flow edge-water reservoirs, laying a theoretical foundation for predicting water invasion in reservoirs; analyzing the changes in dimensionless water invasion in different time periods of example reservoirs under different radii, elastic storage ratios, and crossflow coefficients, and the results can provide reference and guidance for predicting water invasion in the future for the reservoir.

Description

Technical Field

[0001] The invention relates to the technical field of petroleum exploration and development, and in particular to a method for drawing dimensionless water invasion maps of fracture-cavity carbonate rock edge-water reservoirs. Background Art

[0002] Carbonate rocks contain abundant oil and gas resources and are an important branch of oil and gas exploration and development in my country. Carbonate reserves account for about 40% of the world's total oil and gas reserves, and the remaining recoverable reserves account for about 47%, and its production accounts for about 60%. Carbonate reservoirs are highly heterogeneous and the development of fractures and caves is uneven. Their reservoir space is even more complex and diverse, including: fracture type, fracture-dissolution pore type, fracture-dissolution cave type and dissolution pore-fracture-dissolution cave type. Among them, the fracture-cavity type reservoir with both fractures and caves is the most important one.

[0003] With the progress of development and the invasion of edge water, the water invasion amount must be calculated in both the reserve calculation and the dynamic prediction process. The size of the water invasion amount can be predicted based on the dimensionless water invasion map, but most of the current dimensionless maps are for sandstone reservoirs, and there is no dimensionless water invasion map for fracture-cavity carbonate reservoirs. Therefore, this paper establishes a dimensionless map drawing method for edge water reservoirs based on fracture-cavity carbonate rocks. Summary of the invention

[0004] In order to overcome the problems in the prior art, the present invention provides a method for drawing a dimensionless water invasion map of a fracture-vuggy carbonate edge-water reservoir.

[0005] The technical solution provided by the present invention to solve the above technical problems is: a method for drawing a dimensionless water invasion map of a fracture-cavity carbonate rock edge-water reservoir, comprising the following steps:

[0006] Step S1, obtaining basic parameters of matrix, fractures and caves, and basic reservoir parameters by collecting on-site reservoir and geological data;

[0007] Step S2: Obtain dimensionless water body radius r according to basic reservoir parameters aD ;

[0008] Step S3: Obtain the matrix-to-crack flow coefficient λ according to the basic parameters of the matrix, cracks and caves mf , the flow coefficient λ of the flow from cave to crack vf , elastic storage ratio of matrix system ω m , elastic storage ratio of fracture system ω f 、Elastic storage capacity ratio of cave systemω v ;

[0009] Step S4, establishing a plane radial flow mathematical model for a fracture-cavity triple medium edge water reservoir;

[0010]

[0011]

[0012]

[0013] Where: m is the matrix elastic storage ratio, dimensionless; r D is the dimensionless radial radius; r aD is the dimensionless water body radius; ω v is the cave elastic storage ratio, dimensionless; is the dimensionless water intrusion of the infinite water body; is the dimensionless water intrusion of the closed water body; u is the Laplace variable; I0 is the first-order modified Bessel function of the first kind; I1 is the first-order modified Bessel function of the first kind; K0 is the second-order zero-order modified Bessel function; K1 is the second-order first-order modified Bessel function; λ mf is the flow coefficient from matrix to fracture; vf is the flow coefficient from cave to fracture;

[0014] Step S5, drawing a dimensionless water intrusion map based on the plane radial flow mathematical model of the fracture-cavity triple medium edge water reservoir.

[0015] A further technical solution is that the basic parameters of the matrix, cracks and caves include matrix shape factor, cave shape factor, matrix system permeability, cave system permeability, crack system permeability, crack system porosity, matrix system porosity, cave system porosity, crack comprehensive compression coefficient, matrix comprehensive compression coefficient, and cave comprehensive compression coefficient.

[0016] A further technical solution is that the basic parameters of the oil reservoir include the oil reservoir radius and the water body radius.

[0017] A further technical solution is that the calculation formula of the dimensionless water body radius is:

[0018] r aD =r a / r o

[0019] Where: r a is the radius of the water body, m; r o is the reservoir radius, m; r aD is the dimensionless water body radius.

[0020] A further technical solution is that the calculation formula of the crossflow coefficient of the matrix to the crack is:

[0021]

[0022] Where: α m is the matrix shape factor, 1 / m 2 ; r w is the well radius, m; k m is the matrix system permeability, μm 2 ;k f is the fracture system permeability, μm 2 ; mf is the flow coefficient from matrix to fracture.

[0023] A further technical solution is that the calculation formula of the flow coefficient of the cave to fracture flow is:

[0024]

[0025] Where: α v is the cave shape factor, 1 / m 2 ;k v is the permeability of the cave system, μm 2 ; r w is the well radius, m; k f is the fracture system permeability, μm 2 ; vf is the flow coefficient from cave to fracture.

[0026] A further technical solution is that the calculation formula of the elastic storage ratio of the fracture system is:

[0027]

[0028] Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω f is the elastic storage ratio of the fracture, dimensionless.

[0029] A further technical solution is that the calculation formula of the elastic storage capacity ratio of the matrix system is:

[0030]

[0031] Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, decimal; φ v is the porosity of the cave system, a decimal; C ftis the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω m is the matrix elastic storage ratio, dimensionless.

[0032] A further technical solution is that the calculation formula of the elastic storage capacity ratio of the cave system is:

[0033]

[0034] Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω v is the cave elastic storage ratio, dimensionless.

[0035] The present invention has the following beneficial effects: the present invention draws the relationship curve between dimensionless water invasion and dimensionless time in infinite water body and closed water body plane radial flow edge water reservoir, laying a theoretical foundation for predicting water invasion in reservoir; the present invention analyzes the change of dimensionless water invasion in different time of example reservoir under different radius, elastic storage volume ratio and crossflow coefficient, and the result can provide reference and guidance for predicting water invasion in the reservoir in the future.

[0036] The invention is suitable for predicting water intrusion in fracture-cavity type plane radial flow edge water reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a physical model of plane radial flow water invasion in fracture-cavity carbonate edge water reservoir of the present invention;

[0038] Figure 2 It is a relationship curve between dimensionless water intrusion and dimensionless time of radial flow of edge water in limited closed water body of fracture-cavity carbonate reservoir in the present invention;

[0039] Figure 3 It is the relationship curve between dimensionless water intrusion and dimensionless time of the radial flow of infinite water body edge water in the fracture-cavity carbonate reservoir of the present invention;

[0040] Figure 4 is the radius r of different dimensionless water bodies in the present invention aD The relationship curve between the dimensionless water intrusion and the dimensionless time of the edge water radial flow in the lower fracture-cavity carbonate reservoir;

[0041] Figure 5 is the elastic storage ratio of different fracture systems in the present invention ω f The influence of water intrusion on fracture-cavity carbonate reservoirs with limited confinement and edge water;

[0042] Figure 6 is the elastic storage ratio of different fracture systems in the present invention ω f The influence of water intrusion on infinite edge water reservoirs in fracture-vuggy carbonate rocks;

[0043] Figure 7 is the elastic storage ratio of different cave systems in the present invention ω v The influence of water intrusion on fracture-cavity carbonate reservoirs with limited confinement and edge water;

[0044] Figure 8 is the elastic storage ratio of different cave systems in the present invention ω v The influence of water intrusion on infinite edge water reservoirs in fracture-vuggy carbonate rocks;

[0045] Fig. 9 is the flow coefficient λ of different caves to cracks in the present invention vf The influence of water intrusion on fracture-cavity carbonate reservoirs with limited confinement and edge water;

[0046] Fig.10 is the flow coefficient λ of different caves to cracks in the present invention vf The influence of water intrusion on infinite edge water reservoirs in fracture-vuggy carbonate rocks;

[0047] Fig.11 is the crossflow coefficient λ of different matrices to the cracks in the present invention mf The influence of water intrusion on fracture-cavity carbonate reservoirs with limited confinement and edge water;

[0048] Fig.12 is the crossflow coefficient λ of different matrices to the cracks in the present invention mf Influence of water intrusion on infinite edge water reservoirs in fracture-vuggy carbonate rocks. DETAILED DESCRIPTION

[0049] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The method for drawing dimensionless water invasion maps of fracture-cavity carbonate edge-water reservoirs of the present invention comprises the following steps:

[0051] Step S1, obtaining basic parameters of matrix, fractures and caves, and basic reservoir parameters by collecting on-site reservoir and geological data;

[0052] The basic parameters of the matrix, fractures and caves include matrix shape factor, cave shape factor, matrix system permeability, cave system permeability, fracture system permeability, fracture system porosity, matrix system porosity, cave system porosity, fracture comprehensive compression coefficient, matrix comprehensive compression coefficient, and cave comprehensive compression coefficient;

[0053] The basic parameters of the oil reservoir include the radius of the oil reservoir and the radius of the water body;

[0054] Step S2: Obtain dimensionless water body radius r according to basic reservoir parameters aD ;

[0055] r aD =r a / r o

[0056] Where: r o is the reservoir radius, m; r a is the radius of the water body, m; r aD is the dimensionless water body radius;

[0057] Step S3: Obtain the matrix-to-crack flow coefficient λ according to the basic parameters of the matrix, cracks and caves mf , the flow coefficient λ of the flow from cave to crack vf , elastic storage ratio of matrix system ω m , elastic storage ratio of fracture system ω f 、Elastic storage capacity ratio of cave systemω v ;

[0058]

[0059]

[0060] Where: α m is the matrix shape factor, 1 / m 2 ; r w is the well radius, m; k m is the matrix system permeability, μm 2 ;k f is the fracture system permeability, μm 2 ; mf is the flow coefficient from matrix to fracture; α v is the cave shape factor, 1 / m 2 ;k v is the permeability of the cave system, μm 2 ; vf is the flow coefficient from cave to fracture;

[0061]

[0062]

[0063]

[0064] Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω f is the elastic storage ratio of the fracture, dimensionless; ω m is the matrix elastic storage ratio, dimensionless; ω v is the cave elastic storage ratio, dimensionless;

[0065] Step S4, establishing a plane radial flow mathematical model for a fracture-cavity triple medium edge water reservoir;

[0066]

[0067]

[0068]

[0069] Where: m is the matrix elastic storage ratio, dimensionless; r D is the dimensionless radial radius; r aD is the dimensionless water body radius; ω v is the cave elastic storage ratio, dimensionless; is the dimensionless water intrusion of the infinite water body; is the dimensionless water intrusion of the closed water body; u is the Laplace variable; I0 is the first-order modified Bessel function of the first kind; I1 is the first-order modified Bessel function of the first kind; K0 is the second-order zero-order modified Bessel function; K1 is the second-order first-order modified Bessel function; λ mf is the flow coefficient from matrix to fracture; vf is the flow coefficient from cave to fracture;

[0070] The specific process of establishing the model is as follows:

[0071] Step 41: The differential mathematical model of the homogeneous seepage system is:

[0072]

[0073] Where: p fD is the dimensionless pressure of the fracture system; r D is the dimensionless radial radius; λ mf is the matrix to crack flow coefficient; vf is the flow coefficient from cave to crack; p mD is the dimensionless pressure of the matrix system; p vD is the dimensionless pressure of the cave system; ω f is the elastic storage ratio of the fracture, dimensionless; t D is dimensionless time;

[0074] Step S42: Determine the initial conditions and internal and external boundary conditions of the reservoir:

[0075] The initial reservoir conditions are:

[0076] Internal boundary conditions (constant bottom hole pressure production):

[0077] External boundary condition: p fD (∞,t D )=0(infinite water)

[0078]

[0079] Step S43: Introduce t-based D Laplace transform:

[0080]

[0081]

[0082]

[0083] The calculation formula for the dimensionless time of radial flow is:

[0084]

[0085] Where: k is the permeability of the reservoir rock, D; μ w is the viscosity of formation water, mPa·s; t is the production time, ks;

[0086] Step S44, discretizing the pressure drop process to obtain a dimensionless water intrusion integral form;

[0087]

[0088] Step S45: Change the differential equation in step S43 to:

[0089]

[0090]

[0091] Where: m is the matrix elastic storage ratio, dimensionless; ω v is the cave elastic storage ratio, dimensionless;

[0092] Step S46: Change the -λ in step S45 mf Substituting the equation of f(u) into the differential equation yields:

[0093]

[0094] make

[0095]

[0096] The above equation is a v-order imaginary Bessel equation, and its general solution is:

[0097] y=AI v (x)+BK v (x)

[0098] This equation is a Bessel equation of order 0;

[0099] Step S47, substituting the (infinite) outer boundary condition into the Bessel equation to obtain the general solution of pressure:

[0100]

[0101] According to the properties of Bessel function, A=0;

[0102] Therefore, the general solution for pressure can be written as:

[0103]

[0104] Step S48, substituting the internal boundary condition into the pressure general solution of step S47, we can obtain:

[0105]

[0106]

[0107] Step S49: The dimensionless water intrusion model of the infinite water body is:

[0108]

[0109] Step S410, substituting the boundary conditions outside the closed water body into the Bessel equation in step S46, we can obtain:

[0110]

[0111]

[0112]

[0113] By solving the matrix, we can get A and B:

[0114]

[0115]

[0116] Step S110, dimensionless water intrusion model of closed water body;

[0117]

[0118] Step S5, drawing a dimensionless water influx chart according to the plane radial flow mathematical model of the fracture-cavity triple medium edge water reservoir, specifically, programming based on the solution of the mathematical model based on the Visual Basic language, inputting the obtained parameters into the programming to draw the relationship curve between the dimensionless water influx of the finite closed water body homogeneous reservoir and the fracture-cavity reservoir and the time change, and drawing the relationship curve between the dimensionless water influx of the infinite water body homogeneous reservoir and the fracture-cavity reservoir and the time change.

[0119] Example

[0120] Step S10, by collecting on-site reservoir and geological data, obtaining basic parameters of matrix, fractures and caves, and basic reservoir parameters;

[0121] Step S20: Calculate the dimensionless water body radius r according to the above parameters aD =2; the matrix to fracture cross-flow coefficient λ mf 1.32×10 -7 , the flow coefficient λ of the flow from cave to crack vf 1.44×10 -6 , elastic storage ratio of fracture system ω f is 0.01, and the elastic storage capacity ratio of the matrix system ω m is 0.2, the elastic storage capacity ratio of the cave system ω v is 0.2;

[0122] Step S30, establishing and solving a plane radial flow water invasion mathematical model for a fracture-cavity triple medium edge water reservoir, and performing programming according to the solution of the mathematical model;

[0123] Step S40: Input the calculated parameters into the programming of the solution of the mathematical model to draw the relationship curve between the dimensionless water intrusion of the finite closed water body homogeneous reservoir and the fracture-cavity reservoir and the time change (such as Figure 2As shown in the figure), the relationship curves of dimensionless water intrusion of infinite water body homogeneous reservoir and fracture-cavity reservoir with time are drawn (as shown in the figure). Figure 3 shown).

[0124] In this example, in order to study the factors affecting the dimensionless water intrusion, the following experiments were performed respectively;

[0125] The dimensionless water body radius in the programming is set to 1.2, 1.5, 2, 10, 50, and 100 respectively, and other parameters remain unchanged. The relationship curve of dimensionless water intrusion of fracture-cavity carbonate edge water reservoir with time is drawn (such as Figure 4 shown).

[0126] The elastic storage ratio of the fracture system in the programming is set to 0.001, 0.01, 0.05, and 0.2 respectively, and other parameters remain unchanged. The relationship curve of the dimensionless water intrusion of the finite closed water body fracture-cavity reservoir with time is drawn, and the relationship curve of the dimensionless water intrusion of the infinite water body fracture-cavity reservoir with time is drawn (such as Figure 5 , 6 shown).

[0127] The elastic storage ratio of the karst cave system in the programming is set to 0.001, 0.01, 0.05, and 0.2 respectively, and other parameters remain unchanged. The relationship curve of the dimensionless water intrusion of the finite closed water body fracture-cavity reservoir with time is drawn, and the relationship curve of the dimensionless water intrusion of the infinite water body fracture-cavity reservoir with time is drawn (such as Figure 7 , 8 shown).

[0128] The flow coefficient from the cave to the crack in the programming is set to 1×10 -10 , 1×10 -3 , 1, 20, other parameters remain unchanged, draw the relationship curve of dimensionless water influx of finite closed water body fracture-cavity reservoir with time, draw the relationship curve of dimensionless water influx of infinite water body fracture-cavity reservoir with time (such as Fig. 9 , 10 shown).

[0129] The matrix-to-fracture crossflow coefficients in the programming are set to 1×10 -10 , 1×10 -3 , 1, 20, other parameters remain unchanged, draw the relationship curve of dimensionless water influx of finite closed water body fracture-cavity reservoir with time, draw the relationship curve of dimensionless water influx of infinite water body fracture-cavity reservoir with time (such as Fig.11 , 12 shown).

[0130] Sensitivity analysis

[0131] 1. For reservoirs with limited enclosed water bodies, the water influx of homogeneous reservoirs in the early stage is higher than that of fracture-cavity reservoirs. The change of water influx in fracture-cavity reservoirs is greatly affected by the crossflow coefficient and elastic storage ratio. For reservoirs with infinite water bodies, the water influx increases with time, but the water influx of homogeneous reservoirs in the early stage is higher than that of fracture-cavity reservoirs.

[0132] 2. For a finite closed water reservoir, the dimensionless water invasion increases with time. The larger the dimensionless radius, the greater the water invasion of the reservoir. For a reservoir with an infinite water body, the change in water invasion is not affected by the dimensionless radius.

[0133] 3. Different elastic storage ratios. For fracture-cavity reservoirs, the larger the elastic storage ratio of the fracture system, the greater the water invasion. For reservoirs with limited enclosed water bodies, the water invasion will tend to be stable in the later stage.

[0134] 4. The larger the crossflow coefficient, the larger the dimensionless water invasion of the fracture-vuggy reservoir. For reservoirs with finite closed boundaries, the water invasion will remain unchanged in the later stage.

[0135] Related conclusions

[0136] For infinite horizontal radial flow fracture-cavity reservoirs, when the elastic storage ratio and crossflow coefficient remain unchanged, the dimensionless water invasion does not change when the dimensionless water body radius is different; when the water body radius is constant, the dimensionless water invasion increases with the increase of the elastic storage ratio and crossflow coefficient.

[0137] For closed boundary horizontal plane radial flow fracture-cavity reservoirs, when the elastic storage capacity ratio and crossflow coefficient remain unchanged, the dimensionless water invasion increases with the increase of water body radius, and the curve gradually moves upward; when the water body radius is constant, the dimensionless water invasion increases with the increase of elastic storage capacity ratio and crossflow coefficient.

[0138] For edge water radial flow fracture-cavity reservoirs, water invasion is affected by the elastic storage ratio and crossflow coefficient. With the increase of elastic storage ratio and crossflow coefficient, water invasion increases continuously. Closed boundary edge water radial flow fracture-cavity reservoirs are also affected by the dimensionless water body radius. With the increase of water body radius, water invasion gradually increases; while for infinite edge water reservoirs, water invasion is not affected by water body radius.

[0139] The above description is not intended to impose any form of limitation on the present invention. Although the present invention has been disclosed through the above embodiments, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A method for drawing dimensionless water invasion maps of fracture-cavity carbonate edge-water reservoirs, characterized in that: The following steps are involved: Step S1, obtaining basic parameters of matrix, fractures and caves, and basic reservoir parameters by collecting on-site reservoir and geological data; Step S2: Obtain dimensionless water body radius r according to basic reservoir parameters aD ; r aD ＝r a / r o Where: r a is the radius of the water body, m; r o is the reservoir radius, m; r aD is the dimensionless water body radius; Step S3: Obtain the matrix-to-crack flow coefficient λ according to the basic parameters of the matrix, cracks and caves mf , the flow coefficient λ of the flow from cave to crack vf , elastic storage ratio of matrix system ω m , elastic storage ratio of fracture system ω f 、Elastic storage capacity ratio of cave systemω v ; The calculation formula of the matrix to crack flow coefficient is: Where: α m is the matrix shape factor, 1 / m 2 ; r w is the well radius, m; k m is the matrix system permeability, μm 2 ;k f is the fracture system permeability, μm 2 ; λ mf is the flow coefficient from matrix to fracture; The calculation formula of the flow coefficient from the cave to the crack is: Where: α v is the cave shape factor, 1 / m 2 ;k v is the permeability of the cave system, μm 2 ; r w is the well radius, m; k f is the fracture system permeability, μm 2 ; λ vf is the flow coefficient from cave to fracture; The calculation formula of the elastic storage ratio of the fracture system is: Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, a decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω f is the elastic storage ratio of the fracture, dimensionless; The calculation formula of the elastic storage capacity ratio of the matrix system is: Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, a decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω m is the matrix elastic storage ratio, dimensionless; The calculation formula of the elastic storage capacity ratio of the cave system is: Where: φ f is the porosity of the fracture system, decimal; φ m is the porosity of the matrix system, a decimal; φ v is the porosity of the cave system, a decimal; C ft is the comprehensive compression coefficient of cracks, 1 / MPa; C mt is the comprehensive compression coefficient of the matrix, 1 / MPa; C vt is the comprehensive compression coefficient of the cave, 1 / MPa; ω v is the cave elastic storage ratio, dimensionless; Step S4, establishing a plane radial flow mathematical model for a fracture-cavity triple medium edge water reservoir; Where: m is the matrix elastic storage ratio, dimensionless; r D is the dimensionless radial radius; r aD is the dimensionless water body radius; ω v is the cave elastic storage ratio, dimensionless; is the dimensionless water intrusion of the infinite water body; is the dimensionless water intrusion of the closed water body; u is the Laplace variable; I0 is the first-order modified Bessel function of the first kind; I1 is the first-order modified Bessel function of the first kind; K0 is the second-order zero-order modified Bessel function; K1 is the second-order first-order modified Bessel function; λ mf is the flow coefficient from matrix to fracture; vf is the flow coefficient from cave to fracture; Step S5, drawing a dimensionless water intrusion map based on the plane radial flow mathematical model of the fracture-cavity triple medium edge water reservoir.

2. The method for drawing dimensionless water invasion maps of fracture-cavity carbonate edge-water reservoirs according to claim 1, characterized in that: The basic parameters of the matrix, cracks and caves include matrix shape factor, cave shape factor, matrix system permeability, cave system permeability, crack system permeability, crack system porosity, matrix system porosity, cave system porosity, crack comprehensive compression coefficient, matrix comprehensive compression coefficient, and cave comprehensive compression coefficient.

3. The method for drawing dimensionless water invasion maps of fracture-cavity carbonate edge-water reservoirs according to claim 1, characterized in that: The basic parameters of the oil reservoir include the oil reservoir radius and the water body radius.

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