Fractured carbonate reservoir physical model and preparation method and application thereof

Abstract

The invention provides a fractured carbonate reservoir physical model and a preparation method and application thereof, and relates to the technical field of oil and gas development. The preparation method of the reservoir physical model comprises the steps of matrix rock preparation, cutting and splicing, fracture width control and model assembly scheme. The method comprises the following steps: preparing matrix rocks according to specific lithologic characteristics of an actual oil reservoir, cutting the matrix rocks into fragments similar to oil reservoir blocks, and orderly splicing the fragments; gaskets are arranged between the matrix rock fragments, different crack widths are formed through control of the gaskets with different thicknesses, finally, the outside of a cylinder formed by the matrix rock fragments is fixed, and the crack type carbonate reservoir model is formed. The model has lithologic characteristics, channel characteristics, wettability characteristics and mechanical strength of an actual reservoir, provides a reliable experimental model for physical simulation experiments of oil reservoirs, obtains experimental results more conforming to actual production characteristics of the oil reservoirs, and can be widely applied to physical simulation experiments or structural characteristic researches of fractured and fractured-vuggy oil reservoirs.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil and gas development, and in particular relates to a fractured carbonate reservoir physical model, a preparation method and an application thereof. Background Art

[0002] Fault-controlled carbonate reservoirs represent a highly promising oil and gas reservoir type and represent a key area for exploration and production enhancement. These reservoirs exhibit unique characteristics in terms of reservoir structure, reservoir model, and flow patterns. The patterns of oil and water movement within these reservoir structures have yet to be systematically studied. Physical simulation experiments are needed to determine movement parameters under basic model conditions, summarize these patterns, and then validate and apply them using actual production data.

[0003] Currently, research on fracture-cavity structures in fault-controlled reservoirs, particularly physical simulation experiments, is still in its infancy. Existing fracture models or testing devices are mostly microfractures or fractures formed by hydraulic fracturing in sandstone or shale. No specific physical modeling techniques have been developed for large-scale fractures in carbonate rocks. Some studies have employed techniques such as cavity-setting equipment, glass etching, and 3D printing to simulate fracture pathways. However, the models generated by these techniques generally lack the physical properties and mechanical strength of the reservoir rock, making them incapable of conducting tests under actual reservoir temperatures and pressures.

[0004] Chinese invention patent CN107165624B discloses a three-dimensional, large-scale physical model of a fracture-cavity carbonate reservoir and its preparation method. The physical model consists of simulated caves, simulated fractures, and a constant-temperature oven. The simulated caves consist of a reactor and a carbonate outcrop core. The carbonate outcrop core, which has natural cavities, undergoes wettability testing, mineral composition testing, and CT scanning analysis, is cut and shaped, and then loaded into the reactor. Both ends of the reactor are sealed with reactor screens for sand control. The simulated fractures consist of pipelines and carbonate particles. The carbonate particles are filled into the pipelines and compacted. Both ends of the pipelines are sealed with pipeline screens. A back-pressure valve is installed on the side of the constant-temperature oven, housing the simulated caves and fractures. The back-pressure valve is connected to the outlet pipeline. The simulated caves are connected to each other through the simulated fractures, and the simulated fractures are connected to each simulated cave via valves. During the simulation process, this physical model lacks fidelity in the fracture simulation.

[0005] Chinese invention patent CN108590642B discloses a filling design method for a three-dimensional physical model of a fracture-vuggy carbonate reservoir, comprising the following steps: step S1, constructing a three-dimensional cavity physical model of a target area of ​​a fracture-vuggy carbonate reservoir; step S2, determining the filling position, filling internal structure, and vertical physical property distribution characteristics; step S3, determining the filling degree based on seismic reflection characteristics, logging curve interpretation, and geological modeling porosity model; step S4, selecting a filling material and a binder to fill the three-dimensional cavity physical model; the specific steps of step S3 are: judging the structure of the target area of ​​the fracture-vuggy carbonate reservoir; when the structural type of the target area of ​​the fracture-vuggy carbonate reservoir is a cave, determining the filling degree by the following method Filling degree; (1) When the cave is controlled by a single well, the filling degree is determined by the volume of the fracture-cavity body controlled by the single well, the liquid volume controlled by the single well, and the total volume of the fracture-cavity body controlled by the single well; (2) When the cave has a well logging curve, the porosity is obtained by interpreting the well logging curve, and then the filling degree is obtained by the porosity. The filling degree is the difference between 1 and the porosity; (3) When the cave has no well logging curve, the porosity is obtained by the assignment method, and then the filling degree is obtained by the porosity. The filling degree is the difference between 1 and the porosity; when the structural type of the target area of ​​the fracture-cavity carbonate reservoir is fracture or dissolution pore, the porosity is determined by interpreting the well logging curve and the geological modeling porosity model, and then the filling degree is obtained by the porosity. The filling degree is the difference between 1 and the porosity. It does not achieve the effective design of the fracture-type reservoir model.

[0006] In addition, utility model patent CN203685173U discloses a three-dimensional macroscopic physical simulation experimental device for fracture-cavity carbonate reservoirs, and provides an epoxy resin method between rock blocks and at the top and bottom to simulate the inlet and outlet channels. However, the patent emphasizes that the cracks and holes inside the rock blocks are more important in the experiment, and it does not clearly propose a method for depicting such actual channels.

[0007] In view of this, in order to provide a reliable experimental model for physical simulation experiments of fault-controlled oil reservoirs, thereby obtaining experimental results that are more consistent with the actual production characteristics of the oil reservoir, provide a theoretical basis for fault-controlled oil reservoir research, and better serve the development, design, and adjustment deployment of fault-controlled oil reservoirs, the present invention designs a method for preparing a reservoir physical model based on the characteristics of fractured reservoirs in fault-controlled oil reservoirs. The physical model is endowed with the lithologic characteristics, channel characteristics, wettability characteristics, and mechanical strength of the actual reservoir. The model can be widely used in physical simulation of fractured oil reservoirs and has broad application prospects. Summary of the Invention

[0008] This invention addresses the problems of the existing technology by providing a physical model of a fractured carbonate reservoir, its preparation method, and its application. Specifically targeting the characteristics of fractured reservoirs in fault-controlled oil reservoirs, a method for preparing a reservoir physical model is designed. This model incorporates the lithologic, channel, wettability, and mechanical strength characteristics of actual reservoirs, providing a reliable experimental model for physical simulation experiments of such reservoirs. This model can yield experimental results that are more consistent with the reservoir's actual production characteristics, providing a theoretical basis for research on fault-controlled reservoirs and better serving the development, design, and adjustment deployment of such reservoirs. The model is widely applicable to physical simulation experiments or structural feature research of fractured and fracture-cavity reservoirs.

[0009] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0010] First, the present invention provides a method for preparing a physical model of a fractured carbonate reservoir, including: a matrix rock preparation scheme, a cutting and splicing scheme, a fracture width control scheme and a model assembly scheme.

[0011] Preferably, the matrix rock preparation scheme is: prepare the matrix rock according to the specific lithologic characteristics of the actual oil reservoir; the matrix rock is a dense carbonate rock, a natural rock, and is selected from at least one of limestone, dolomite, dolomitic limestone, sandy limestone, muddy limestone, gray dolomite, sandy dolomite, and muddy dolomite.

[0012] Further preferably, the matrix rock conforms to the actual reservoir characteristics in terms of mechanical properties, rock physical properties, especially wettability; by comparing the results of rock and mineral testing, rock mechanics testing, wettability testing and oil reservoir testing, the most similar matrix rock is selected for use.

[0013] Preferably, the matrix rock is configured to have two flattened cylinders before use, with a diameter Φ ≥ 10 cm and a length L ≥ 30 cm. Finally, the matrix rock is configured to be used in a conventional full-diameter core testing instrument, or according to the size of the holder or reaction chamber of the testing instrument.

[0014] More preferably, the diameter of the cylinder is Φ10-20 cm, and the length L is 30-40 cm.

[0015] Preferably, the cutting and splicing scheme is as follows: based on the fracture development characteristics of the actual oil reservoir or the seismic carving results, abstract and simplify to form a fracture characteristic model, and quantify the reservoir blockiness after fracture cutting; then cut the matrix rock into individual matrix rock fragments that are analogous to the oil reservoir blocks; after orderly splicing the matrix rock fragments, finally restore the external shape before cutting, that is, preliminarily form a fracture-type carbonate reservoir physical model with fractures as the main channels.

[0016] Further preferably, the fracture characteristic model includes single fractures, orthogonal fractures, parallel fractures and fracture networks.

[0017] Preferably, the crack width control scheme is: arranging gaskets between matrix rock fragments, and controlling the formation of different crack widths by arranging gaskets of different thicknesses, thereby obtaining matrix rock fragments that are well spliced ​​and have controlled crack widths.

[0018] Further preferably, the gasket is a high-strength fixed-thickness micro gasket.

[0019] More preferably, the diameter of the high-strength fixed-thickness micro-gasket is ≤1mm, the thickness of the high-strength fixed-thickness micro-gasket is different, the thickness range of each high-strength fixed-thickness micro-gasket is 0.1-3mm, and the bearing pressure of a single high-strength fixed-thickness micro-gasket is ≥30MPa.

[0020] More preferably, the diameter of the high-strength fixed-thickness micro-gasket is 0.5-1 mm, and the bearing pressure of a single high-strength fixed-thickness micro-gasket is 30-42 MPa.

[0021] More preferably, the high-strength fixed-thickness micro-gaskets have different thicknesses, not limited to 0.1 mm, 0.2 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm or 3 mm.

[0022] Further preferably, the crack width is controlled so that it will not close during the experiment due to the high strength of the gasket, and thus can be used to test the effect of the crack width on the flow law under reservoir temperature and pressure conditions.

[0023] In the present invention, the cracks within the crack width can be filled with fillers of different properties in the middle and late stages; the crack width parameters of the present invention are fully controllable and remain stable during the experiment, thereby obtaining a more realistic crack simulation effect.

[0024] Preferably, the model assembly scheme is: fixing the matrix rock fragments that have been spliced ​​and have controlled the crack width after the cutting and splicing scheme and the crack width control scheme outside the cylinder to form a complete fractured carbonate reservoir model that can be placed in an instrument for testing.

[0025] Further preferably, a heat shrink tube is used for the fixing.

[0026] In the present invention, the heat shrink tube can wrap the model, so that the rock blocks inside the model fit more tightly and the overall shape of the model is flatter; the model wrapped with the heat shrink tube can protect the rubber sleeve inside the core holder.

[0027] Then, the present invention provides a fractured carbonate reservoir physical model prepared by the above preparation method.

[0028] Finally, the present invention provides the application of the above-mentioned fractured carbonate reservoir physical model in physical simulation experiments or structural characteristics research of fractured and fracture-cavity oil reservoirs.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The preparation method of the fractured carbonate reservoir physical model of the present invention uses natural rock as the basic material. Compared with the raw materials of existing glass etching, 3D printing and other technologies, it can better achieve similarity and consistency with the actual oil reservoir in terms of lithology, rock mechanical properties, wettability and other characteristics.

[0031] 2. The reservoir physical model formed by the matrix rock and high-strength micro-gaskets in the present invention can withstand temperature and pressure changes that are more consistent with reservoir conditions compared to the mechanical strength of existing models such as glass etching and 3D printing.

[0032] 3. In the preparation method of the fractured carbonate reservoir physical model of the present invention, the cutting scheme adopted is derived from the crack carving results of actual oil reservoirs, and high-strength micro-gaskets are used to control the crack width. Compared with natural cracks in rocks, which may experience a decrease in crack width under high confining pressure, the fractured carbonate reservoir physical model prepared by the present invention can still maintain the set crack width under high confining pressure, thereby obtaining a more accurate fracture permeability relationship.

[0033] 4. The fractured carbonate reservoir physical model provided by the present invention is a reservoir physical model that conforms to the actual reservoir characteristics of fractured carbonate rocks. It is a reservoir physical model designed based on the reservoir structural characteristics of carbonate oil reservoirs with fractures as the main flow channels. It is mainly used in physical simulation experiments or structural characteristic research of fractured and fracture-cavity oil reservoirs. It has the characteristics of controllable physical properties, convenient operation, and strong mechanical properties, and has broad prospects for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a schematic diagram of a matrix rock cylinder.

[0035] Figure 2 It is a schematic flow chart of the cutting and splicing solution of the present invention.

[0036] Figure 3 This is a schematic diagram of the crack model after crack width control. DETAILED DESCRIPTION

[0037] The following non-limiting examples can make those of ordinary skill in the art understand the present invention more comprehensively, but do not limit the present invention in any way. The following content is merely an exemplary description of the scope of protection of the present invention, and those skilled in the art can make various changes and modifications to the present invention based on the disclosed content, and they should also fall within the scope of protection of the present invention. When the embodiments provide numerical ranges, it should be understood that, unless otherwise specified in the present invention, the two endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those of ordinary skill in the art to which the present invention belongs.

[0038] The invention provides a method for preparing a fractured carbonate reservoir physical model, comprising: a matrix rock preparation scheme, a cutting and splicing scheme, a fracture width control scheme and a model assembly scheme.

[0039] (1) The matrix rock preparation scheme is as follows: prepare the matrix rock according to the specific lithologic characteristics of the actual oil reservoir; the matrix rock is a dense carbonate rock, which is a natural rock and is selected from at least one of limestone, dolomite, dolomitic limestone, sandy limestone, muddy limestone, gray dolomite, sandy dolomite, and muddy dolomite.

[0040] The matrix rock should be consistent with the actual reservoir characteristics in terms of mechanical properties, rock physical properties, especially wettability. By comparing the results of rock and mineral testing, rock mechanics testing, wettability testing and reservoir formation testing, the most similar matrix rock should be selected for use. The shape of the matrix rock is used for conventional full-diameter core testing instruments, or it can be set according to the size of the test instrument's holder or reaction chamber. It can be set to two flattened cylinders with a diameter of Φ ≥ 10 cm and a length of L ≥ 30 cm (e.g. Figure 1 shown).

[0041] (2) The cutting and splicing scheme is as follows: Based on the fracture development characteristics of the actual reservoir or the seismic carving results, the fracture characteristic model (including single fracture, orthogonal fracture, parallel fracture, fracture network) is abstracted and simplified, and the reservoir blockiness after fracture cutting is quantified; then the matrix rock is cut into matrix rock fragments that are analogous to the reservoir block; after the matrix rock fragments are spliced ​​in order, they are finally restored to their external form before cutting, that is, a fracture-type carbonate reservoir physical model with fractures as the main channels is initially formed. The specific scheme diagram is as follows Figure 2 shown.

[0042] (3) The crack width control scheme is to set high-strength fixed-thickness micro-gaskets between matrix rock fragments, and to control the formation of different crack widths by setting gaskets of different thicknesses, thus forming a crack model after crack control (such as Figure 3 As shown, Figure 3The points in the middle crack are high-strength fixed-thickness micro-gaskets, and micro-gaskets of different thicknesses are used to control the formation of a stable crack width. The diameter of the high-strength fixed-thickness micro-gasket is ≤1mm, and the thickness of the high-strength fixed-thickness micro-gasket varies, ranging from 0.1-3mm. The pressure bearing capacity of a single high-strength fixed-thickness micro-gasket is ≥30MPa.

[0043] The thickness of the high-strength fixed-thickness micro-gasket is not limited to 0.1mm, 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm, or 3mm. The crack width is controlled so that it does not close during the experiment due to the high strength of the gasket, thereby being used to test the effect of crack width on flow characteristics under reservoir temperature and pressure conditions.

[0044] The cracks in the crack width can be filled with fillers of different properties in the middle and late stages; the crack width parameters of the present invention are fully controllable and remain stable during the experiment, so that a more realistic crack simulation effect can be obtained.

[0045] (4) The model assembly plan is: after the cutting and splicing plan and the fracture width control plan, the matrix rock fragments that have been spliced ​​and the fracture width is controlled are fixed with a reinforced heat shrink tube to form a complete fracture-type carbonate reservoir model that can be placed in the instrument for testing.

[0046] The present invention will be further described below by way of specific embodiments.

[0047] Example 1

[0048] A method for preparing a physical model of a fractured carbonate reservoir includes: a matrix rock preparation scheme, a cutting and splicing scheme, a fracture width control scheme, and a model assembly scheme.

[0049] The matrix rock preparation plan involves preparing matrix rock based on the specific lithologic characteristics of the actual reservoir. The matrix rock is dense carbonate rock, a natural limestone. Its mechanical and petrophysical properties, especially wettability, match the actual reservoir characteristics. By comparing the results of rock and mineral testing, rock mechanics testing, and wettability testing with those of the reservoir formation, similar matrix rock is selected for future use.

[0050] The matrix rock's shape is designed for use with conventional full-diameter core testing instruments, or according to the dimensions of the instrument's holder or reaction chamber. The matrix rock's shape is defined as two flattened cylinders with a diameter of 13 cm and a length of 30 cm. The cutting and splicing scheme is as follows: Based on the actual reservoir's fracture structure, an orthogonal fracture network model is abstracted and simplified to form the model. The size of each orthogonal grid rock block is determined. In this embodiment, the rock is divided into three equal layers vertically, with no horizontal cutting, resulting in a total of nine long strips. Based on this block design, the matrix rock is cut into matrix rock fragments that resemble the reservoir's blocks. The matrix rock fragments are then spliced ​​in an orderly fashion according to their pre-cut positions ( Figure 2 ), it eventually returns to its external form before cutting, that is, a physical model of a fractured carbonate reservoir with fractures as the main channels is initially formed.

[0051] The fracture width control scheme involves placing high-strength, fixed-thickness micro-gaskets between matrix rock fragments. The diameter of each micro-gasket is 0.5 mm, and the bearing capacity of a single micro-gasket is 30 MPa. The thicknesses of the micro-gaskets vary, including 0.2 mm, 0.5 mm, and 2.0 mm. By placing gaskets of varying thickness, different fracture widths are achieved. The high strength of the gaskets prevents the controlled fracture widths from closing during the experiment, allowing for testing the impact of fracture width on flow patterns under reservoir temperature and pressure conditions.

[0052] The crack width parameters are fully controllable and remain stable during the experiment, which can obtain more realistic crack simulation effects.

[0053] The model assembly plan is: after the cutting and splicing plan and the fracture width control plan, the matrix rock fragments that have been spliced ​​and the fracture width is controlled are fixed with heat shrink tubing to form a complete fracture-type carbonate reservoir model that can be placed in the instrument for testing.

[0054] The above-mentioned preparation method can successfully obtain a fractured carbonate reservoir physical model. This reservoir physical model can better achieve similarity with actual oil reservoirs in terms of lithology, rock mechanical properties, wettability and other characteristics, and can withstand temperature and pressure changes that are more consistent with reservoir conditions. The set fracture width can still be maintained under high confining pressure, thereby obtaining a more accurate fracture permeability relationship. This fractured carbonate reservoir physical model is used in physical simulation experiments or structural feature research of fractures and fracture-cavity reservoirs. Compared with conventional core fracture models or etched fracture models, it can better withstand high temperature and high pressure experiments and can effectively ensure that the fracture structure and fracture geometric parameters remain constant during the experiment, thereby more accurately obtaining the flow characteristics of the set fracture parameters.

[0055] Specifically, the pressure bearing strength of a single gasket used in this embodiment is 30 MPa, that is, a single gasket can maintain a stable crack width without deformation under a confining pressure of 30 MPa. A combination of multiple gaskets can withstand higher confining pressures and can effectively simulate the formation pressure of several thousand meters in fractured oil reservoirs. In addition, the high-strength metal material is heat-resistant, which means that the crack space will not deform under the high temperature and high pressure conditions of the simulated reservoir. The high-strength metal material is corrosion-resistant and can also be widely used for experiments with a variety of fluids. Moreover, since the gasket diameter is ≤1 mm, relative to the total length of the crack space of 30 cm, the disturbance of the fluid movement by the gasket is within the error range. The flow parameters obtained by this embodiment can be regarded as the flow parameters of the pure crack space, thereby obtaining a reliable crack flow law.

[0056] Example 2

[0057] Different from Example 1, in the cutting and splicing scheme, the single fracture characteristic model is formed by abstracting and simplifying the fracture development characteristics of the actual reservoir or the seismic carving results, that is, the natural rock column is divided into equal parts longitudinally and not cut horizontally, that is, a total of two semi-cylindrical matrix rock blocks (refer to Figure 2 In the first group, a single crack model, 2-3 high-strength fixed-thickness micro-gaskets are set between the matrix rock blocks. The diameter of the high-strength fixed-thickness micro-gasket is 1 mm, the bearing pressure of a single high-strength fixed-thickness micro-gasket is 30 MPa, and the thickness of the high-strength fixed-thickness micro-gasket is 2 mm, thus forming a single crack model with a stable crack width of 2 mm.

[0058] The rest are the same as in Example 1.

[0059] Technical Effect: This reservoir physical model can better achieve similarity with actual reservoir characteristics in terms of lithology, rock mechanical properties, wettability, and other characteristics, and can withstand temperature and pressure changes more consistent with reservoir conditions. It can also maintain the set fracture width under high confining pressure, thereby obtaining a more accurate fracture permeability relationship.

[0060] Comparative Example 1

[0061] Different from Example 1, the fracture flow experiment is carried out using an intact rock column containing natural fractures, or an intact rock column containing natural fractures treated with sand filling.

[0062] In the reservoir experiment of the above model, after using the same high pressure as in Example 1, the cracks of the samples in the model closed or even deformed, and accurate crack parameters and flow properties could not be obtained.

[0063] For samples that use sand filling to control the fracture width, the sand particles fill most of the flow channels while maintaining the fracture width. The obtained flow parameters are not those of a simple fracture channel but are closer to those of a porous medium. In addition, extrusion deformation will still occur under high pressure. During the flow experiment, the sand particles can also be washed away by the fluid, causing unpredictable movement, and even blocking the flow channel and experimental pipeline.

[0064] Compared with existing conventional technologies and models, in the fracture-type carbonate reservoir physical model of the present invention, the fracture width is controllable and remains unchanged in high-temperature and high-pressure experiments, thereby obtaining accurate fracture parameters and flow properties.

[0065] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Simple modifications or equivalent substitutions of the technical solution of the present invention by ordinary technicians in this field do not deviate from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a physical model of a fractured carbonate reservoir, characterized in that: include: Matrix rock preparation plan, cutting and splicing plan, fracture width control plan and model assembly plan.

2. The preparation method according to claim 1, characterized in that The matrix rock preparation plan is: prepare the matrix rock according to the specific lithologic characteristics of the actual oil reservoir; the matrix rock is a dense carbonate rock, a natural rock, and is selected from at least one of limestone, dolomite, dolomitic limestone, sandy limestone, muddy limestone, gray dolomite, sandy dolomite, and muddy dolomite.

3. The preparation method according to claim 1, characterized in that Before use, the matrix rock is configured to have two flattened cylinders with a diameter Φ≥10 cm and a length L≥30 cm. Finally, the matrix rock is configured to be used in a conventional full-diameter core testing instrument, or according to the size of the test instrument's holder or reaction chamber.

4. The preparation method according to claim 1, characterized in that The cutting and splicing scheme is as follows: based on the fracture development characteristics of the actual reservoir or the results of seismic carving, a fracture characteristic model is abstracted and simplified to form, and the reservoir blockiness after fracture cutting is quantified; then, the matrix rock is cut into matrix rock fragments that are analogous to the reservoir blocks; after orderly splicing the matrix rock fragments, the external shape before cutting is finally restored, that is, a preliminary physical model of a fractured carbonate reservoir with fractures as the main channels is formed.

5. The preparation method according to claim 4, characterized in that The crack characteristic model includes single cracks, orthogonal cracks, parallel cracks and crack networks.

6. The preparation method according to claim 1, characterized in that The crack width control scheme is as follows: spacers are set between matrix rock fragments, and different crack widths are controlled by setting spacers of different thicknesses to obtain matrix rock fragments that are well spliced ​​and have controlled crack widths.

7. The preparation method according to claim 6, characterized in that The gasket is a high-strength fixed-thickness micro gasket; the diameter of the high-strength fixed-thickness micro gasket is ≤1mm, the thickness of the high-strength fixed-thickness micro gasket is different, the thickness range of each high-strength fixed-thickness micro gasket is 0.1-3mm, and the pressure bearing capacity of a single high-strength fixed-thickness micro gasket is ≥30MPa.

8. The preparation method according to claim 7, characterized in that The diameter of the high-strength fixed-thickness micro gasket is 0.5-1mm, and the pressure bearing capacity of a single high-strength fixed-thickness micro gasket is 30-42MPa; the thickness of the high-strength fixed-thickness micro gasket is different, not limited to 0.1mm, 0.2mm, 0.5mm, 1mm, 1.5mm, 2mm or 3mm.

9. The preparation method according to claim 1, characterized in that The model assembly scheme is: fixing the matrix rock fragments that have been spliced ​​and have controlled the fracture width after the cutting and splicing scheme and the fracture width control scheme outside the cylinder to form a complete fracture-type carbonate reservoir model that can be placed in the instrument for testing.

10. A physical model of a fractured carbonate reservoir obtained by the preparation method according to any one of claims 1 to 9.

11. Application of the fractured carbonate reservoir physical model according to claim 10 in physical simulation experiments or structural feature studies of fractured and fracture-vuggy reservoirs.

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