Fracture-vuggy carbonate reservoir well trajectory design method based on seismic response characteristics

Abstract

The invention relates to the technical field of oil and gas field development, in particular to a fracture-vuggy carbonate reservoir well trajectory design method based on seismic response characteristics, which comprises the following steps: selecting a target area; judging the morphological characteristics of the seismic response and the combination mode of various seismic responses; establishing different well spacing modes according to the seismic response morphological characteristics and the combination mode; and according to different well spacing modes, corresponding well trajectory design methods are established. By means of the well trajectory design method, the problem that the drilling success rate of the fracture-vug type carbonate reservoir is low can be effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field development, and in particular to a method for designing well trajectories of fracture-cavity carbonate reservoirs based on seismic response characteristics. Background Art

[0002] Carbonate oil and gas reservoirs occupy an important position in the world, with oil and gas reserves accounting for about 50% of the world's total oil and gas reserves, and oil and gas production accounting for more than 60% of the world's total oil and gas production. Fracture-cavity carbonate oil and gas reservoirs are the main type of carbonate oil and gas reservoirs, and their reservoir types are diverse, including: pore type, cave type, fracture type, fracture-pore type, fracture-cavity type and fracture-cavity type. The development location, scale and distribution characteristics of different types of reservoirs vary greatly, the reservoir continuity is poor, the change is fast, the heterogeneity is extremely strong, and the reservoir seismic response characteristics are complex. At present, the characterization of fracture-cavity carbonate reservoirs in China is mainly qualitative or semi-quantitative, and it is difficult to accurately characterize the location, scale and spatial distribution of fracture-cavity carbonate reservoirs dominated by small-scale fractures and caves, which makes it difficult to select well layout targets, difficult to design horizontal well trajectories, easy to leak or empty drilling, and low drilling success rate.

[0003] According to technical research, the current method for designing well trajectories for fracture-cavity carbonate reservoirs is mainly to arrange and design horizontal wells in the reservoir. Most of the research conducted by domestic and foreign experts and scholars in this regard is through analysis and demonstration of factors such as the position of horizontal wells, the length of horizontal sections, and the orientation of horizontal wells. For example, in the prior art, the Chinese invention patent document with the publication number of CN101936165A and the publication date of January 5, 2011, the technical solution disclosed in the patent document is as follows: select the upper and lower isochronal surfaces near the time when the Caledonian tectonic movement ends and the Hercynian tectonic movement begins, use the contour map to reflect the ancient landform with high in the west and low in the east, and locally develop residual hills and depressions, collect seismic data, invert the profile and inter-well seismic data to determine the small-amplitude structural morphology and evolution process, divide the carbonate reservoir sedimentary subfacies and microfacies types, divide the favorable sedimentary microfacies, use the production of existing production wells and pressure measurement data to determine the reservoir connectivity of each well area, divide the favorable area for well layout, and layout the wells in the area with a reservoir thickness greater than 20m.

[0004] In the prior art, there is a Chinese invention patent document with publication number CN102042010A and publication date May 4, 2011. The technical solution disclosed in the patent document is as follows: a method for determining the development location of carbonate fracture-vuggy reservoirs, which guides the design of horizontal wellbore trajectories by accurately predicting the development location of fracture-vuggy reservoirs, ensuring that the horizontal well trajectory is within ±10m of the top of the carbonate fracture-vuggy reservoir, avoiding complex well conditions caused by uncovering oil and gas layers during drilling, and achieving the purpose of efficient exploration and development.

[0005] In the prior art, a Chinese invention patent document with a publication number of CN107237627A and a publication date of October 10, 2017 is proposed. The technical solution disclosed in the patent document is as follows: a method for well layout in a karst carbonate reservoir. The steps of the method for well layout in a karst carbonate reservoir are as follows: (1) selecting a regional Ordovician karst reservoir as a well layout object; (2) extracting and screening multiple parameters that are sensitive to the reaction of the carbonate karst reservoir; (3) predicting the density of fracture development caused by multi-stage tectonic movements through strain analysis technology; (4) drawing a primitive Ordovician carbonate karst paleo-geomorphological map; (5) determining the reservoir thickness and spatial distribution morphology by using the wave impedance difference of different lithological sections of the Ordovician carbonate rock to determine a reasonable evaluation index, and reflecting that the karst reservoir with relatively consistent information is a development zone through multiple information; (6) selecting a favorable area with a higher evaluation index for well site deployment, which effectively solves the serious heterogeneity problem of the reservoir and provides a reliable basis for well site layout. The well layout method is reasonable.

[0006] The existing carbonate reservoir well trajectory design methods represented by the above patents and journal documents mainly determine the reservoir development location and design horizontal well trajectories. Due to the poor continuity, rapid changes, strong heterogeneity, complex reservoir seismic response characteristics, and diverse spatial combination characteristics of fracture-cavity carbonate reservoirs, the existing well trajectory design methods for penetrating high-quality reservoirs are very likely to cause serious drilling losses or emptying, and the drilling is completed in advance, which fails to achieve the purpose of drilling geological design, has a low drilling success rate, and has a poor development effect. Summary of the invention

[0007] In order to solve the above technical problems, the present invention proposes a well trajectory design method for fracture-cavity carbonate reservoirs based on seismic response characteristics, which can effectively solve the problem of low drilling success rate in fracture-cavity carbonate reservoirs.

[0008] The present invention is achieved by adopting the following technical solutions: The method for designing a well trajectory for a fracture-cavity carbonate reservoir based on seismic response characteristics comprises the following steps: S1. Select the target area; S2. Determine the morphological characteristics of earthquake responses and the combination of various earthquake responses; S3. Establish different well layout patterns according to the morphological characteristics and combination methods of seismic response; S4. Establish corresponding well trajectory design methods according to different well layout patterns.

[0009] Step S1 refers to: selecting a target area according to the plane amplitude attributes of the seismic data.

[0010] Step S1 specifically refers to: selecting a strong amplitude development area as a target area according to the plane amplitude attribute of the seismic data.

[0011] The morphological characteristics of the seismic response in step S2 include a "beaded" response, a "sheet-like" response, and a weak reflection response.

[0012] The morphological characteristics of the seismic response are obtained by classifying the strong amplitude reflections on the seismic section of the target area according to different morphologies.

[0013] The specific method of judging the combination of various seismic responses is: according to the characteristics of different karst fractures and caves in different karst areas, the connectivity between the fractures and caves and the internal structure of the fractures and caves are analyzed, the fractures and caves are spatially grouped in three-dimensional space, and the vertical and horizontal combination methods of various seismic responses are established. The well layout patterns include vertical well layout patterns for isolated large fracture-cavity reservoirs, horizontal well layout patterns for in-bedding multi-fracture-cavity reservoirs, high-angle well layout patterns for multi-layer multi-fracture-cavity reservoirs, horizontal well layout patterns for in-bedding hole-cavity + fracture-cavity reservoirs, and horizontal well layout patterns for in-bedding fracture-hole reservoirs.

[0014] Step S3 specifically refers to: If the seismic response is characterized by a "beaded" response and is discontinuous in the horizontal and vertical directions, then a vertical well layout pattern for isolated large fracture-cavity reservoirs is established; If the morphological characteristics of the seismic response are "beaded" responses, with multiple "beaded" responses continuous in the horizontal direction and discontinuous in the vertical direction, then the horizontal well layout pattern for the multi-fracture-cavity reservoir in the bedding layer is established; If the morphological characteristics of the seismic response are "beaded" responses, and multiple "beaded" responses are continuously distributed in the lateral and vertical directions, then a high-angle well layout pattern for multi-layer, multi-fracture and cave reservoirs is established; If the morphological characteristics of the seismic response are "beaded" and "sheet-like" responses, which are continuous in the horizontal direction but discontinuous in the vertical direction, then the horizontal well layout pattern of the bedding hole-type + fracture-type reservoir is established; If the morphological characteristics of the seismic response are "sheet-like" response or weak reflection response, which is continuous in the horizontal direction but discontinuous in the vertical direction, then a horizontal well layout pattern for the bedding fracture-hole type reservoir is established.

[0015] Step S4 specifically refers to: If it is an isolated large fracture-cavity reservoir vertical well layout mode, deploy vertical wells and control the well trajectory to drill from the middle of the reservoir, and force drilling when leakage or emptying occurs; If the horizontal well layout mode is a multi-fracture-cavity reservoir along the layer, deploy horizontal wells and control the horizontal well trajectory to pass within 10m above the top of the reservoir; If the well layout mode is a multi-layer, multi-fracture-cavity reservoir with a high-angle well, a high-angle well is deployed, and the horizontal well trajectory is controlled to cross obliquely within 10m above the top of each fracture-cavity body; If the horizontal well layout mode is for the bedding-type pore-cavity + fracture-cavity reservoir, then deploy the horizontal wells and control the horizontal well trajectory to drill from the middle of the pore-cavity reservoir with a seismic "sheet" response, and drill into the fracture-cavity reservoir with a "beaded" response at the end. When drilling into the fracture-cavity reservoir, force drilling when leakage or emptying occurs; If the horizontal well layout pattern is a bedding fracture-hole reservoir, then deploy the horizontal wells and control the trajectory of the horizontal wells to drill from the middle of the fracture-hole reservoir with a seismic "sheet-like" response.

[0016] When it is a horizontal well layout pattern for a bedding multi-fracture-cavity reservoir or a high-angle well layout pattern for a multi-layer multi-fracture-cavity reservoir, multiple fracture-cavity bodies can be connected after acidizing or fracturing.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The present invention fully considers that fracture-cavity carbonate reservoirs are diverse in type, the scale of various reservoirs varies greatly, the spatial distribution is extremely uneven, the reservoir heterogeneity is extremely strong, and the seismic response forms of various reservoirs are different. Therefore, the seismic reflection characteristics of various reservoirs in the target area are classified by the seismic response characteristics of various reservoir types of fracture-cavity carbonate rocks. On this basis, a combination of various seismic responses is established, and the well trajectory is designed according to the form and combination of seismic responses. The present invention focuses on fracture-cavity carbonate reservoirs, finds the development location, scale and spatial distribution of fracture-cavity carbonate reservoirs, and combines the current status of drilling engineering technology, using the fracture-cavity space combination mode, to design a complete set of well site deployment and well trajectory design modes, effectively guiding the well site deployment and well trajectory design of fracture-cavity carbonate oil and gas reservoirs, which not only achieves the geological goals of drilling, but also reduces the engineering difficulty, improves the drilling success rate, and improves the single well production capacity, effectively filling the technical gap.

[0018] 2. The well trajectory design method of the present invention is used to guide the well site deployment and well trajectory design of fracture-cavity carbonate reservoirs in the Sichuan Basin, Tarim Basin, and Ordos Basin, and the drilling success rate is increased from about 30% to about 97%.

[0019] The scale of fracture-cavity carbonate oil and gas reservoirs is large, and the exploration and development potential is huge. However, due to the strong heterogeneity, the well location deployment and well trajectory design are difficult. This technology has a wide range of application prospects. This technology can also be used in overseas fracture-cavity and fault-controlled carbonate reservoirs for well location deployment and well trajectory design, playing an important role in the exploration and development of fracture-cavity carbonate oil and gas reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein: Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 The well trajectory design patterns for different reservoir types in the present invention. DETAILED DESCRIPTION

[0021] Example 1 As a basic embodiment of the present invention, the present invention includes a method for designing a well trajectory in a fracture-cavity carbonate reservoir based on seismic response characteristics, comprising the following steps: S1. Select the target area.

[0022] S2. Determine the morphological characteristics of earthquake responses and the combination of various earthquake responses.

[0023] S3. Establish different well layout patterns according to the morphological characteristics and combination of seismic responses.

[0024] S4. Establish corresponding well trajectory design methods according to different well layout patterns.

[0025] Example 2 As a preferred embodiment of the present invention, the present invention includes a method for designing a well trajectory of a fracture-cavity carbonate reservoir based on seismic response characteristics, comprising the following steps: S1. Select the target area: Select the target area based on the plane amplitude attributes of the seismic data.

[0026] S2. Determine the morphological characteristics of the seismic response and the combination of various seismic responses. Specifically, the seismic reflection characteristics of various reservoirs in the target area are classified into "beaded" response, "sheet" response and weak reflection response. On this basis, the vertical and horizontal combination of various seismic responses is established.

[0027] S3. According to the morphological characteristics and combination of seismic responses, different well layout patterns are established, namely, vertical well layout pattern for isolated large fracture-cavity reservoirs, horizontal well layout pattern for bedding multi-fracture-cavity reservoirs, high-angle well layout pattern for multi-layer multi-fracture-cavity reservoirs, horizontal well layout pattern for bedding pore-cavity + fracture-cavity reservoirs, and horizontal well layout pattern for bedding fracture-cavity reservoirs.

[0028] S4. Establish corresponding well trajectory design methods according to different well layout patterns.

[0029] Example 3 As another preferred embodiment of the present invention, the present invention includes a method for designing a well trajectory of a fracture-cavity carbonate reservoir based on seismic response characteristics, comprising the following steps: S1. Select the target area.

[0030] S2. Determine the morphological characteristics of seismic responses and the combination of various types of seismic responses. The combination of quasi-seismic responses also refers to the spatial distribution of fracture-cavity bodies. The morphological characteristics of seismic responses include "beaded" responses, "sheet" responses, and weak reflection responses.

[0031] S3. Different well layout patterns are established according to the morphological characteristics and combination of seismic responses, including vertical well layout pattern for isolated large fracture-cavity reservoirs, horizontal well layout pattern for in-bedding multi-fracture-cavity reservoirs, high-angle well layout pattern for multi-layer multi-fracture-cavity reservoirs, horizontal well layout pattern for in-bedding pore-cavity + fracture-cavity reservoirs, and horizontal well layout pattern for in-bedding fracture-cavity reservoirs.

[0032] S4. Establish corresponding well trajectory design methods according to different well layout patterns. Specifically: if it is an isolated large-scale fracture-cavity reservoir vertical well layout pattern, deploy vertical wells, and control the well trajectory to drill from the middle of the reservoir, and force drilling when leakage or emptying occurs; if it is a horizontal well layout pattern of a layered multi-fracture-cavity reservoir, deploy horizontal wells, and control the horizontal well trajectory to pass within 10m above the top of the reservoir; if it is a multi-layer multi-fracture-cavity reservoir with a high-angle well layout pattern, deploy a high-angle well, and control the horizontal well trajectory to pass obliquely within 10m above the top of each fracture-cavity body. If the horizontal well layout pattern is for bedding-cavity + fracture-hole reservoirs, then deploy horizontal wells, and control the trajectory of the horizontal wells to be drilled from the middle of the cave-type reservoir with a seismic "sheet-like" response, and drill into the fracture-hole reservoir with a "beaded" response at the end. When drilling into the fracture-hole reservoir, force drilling is performed when there is leakage or emptying; If the horizontal well layout pattern is for bedding-fracture-cavity reservoirs, then deploy horizontal wells, and control the trajectory of the horizontal wells to be drilled from the middle of the fracture-cavity reservoir with a seismic "sheet-like" response.

[0033] Example 4 As the best embodiment of the present invention, refer to the attached specification Figure 1 The present invention includes a method for designing a well trajectory of a fracture-cavity carbonate reservoir based on seismic response characteristics, comprising the following steps: S1. Optimize target area: Select the area with strong amplitude development as the target area according to the plane amplitude attributes of seismic data.

[0034] S2. Determine the morphological characteristics of earthquake responses and the combination of various earthquake responses.

[0035] Among them, judging the morphological characteristics of seismic response specifically refers to: classifying the strong amplitude reflections on the seismic profile of the target area according to their different morphologies, and their morphologies can be divided into "beaded" response, "sheet" response and weak reflection response.

[0036] Determining the combination of various seismic responses specifically refers to: according to the characteristics of different karst fractures and caves in different karst areas, analyzing the connectivity between the fractures and caves and the internal structure of the fractures and caves, spatially grouping the fractures and caves in three-dimensional space, establishing the longitudinal and transverse combination of various seismic responses, and providing fracture-cavity spatial combinations for well deployment.

[0037] S3. Establish different well layout patterns according to the seismic response morphological characteristics and combination methods. Specifically: If the morphological characteristics of the seismic response are "beaded" responses and are discontinuous laterally and vertically, this is an isolated large-scale fracture-cavity reservoir, and a vertical well layout pattern for isolated large-scale fracture-cavity reservoirs should be established.

[0038] If the morphological characteristics of the seismic response are "beaded" responses, with multiple "beaded" responses continuous in the horizontal direction and discontinuous in the vertical direction, this is a bedding multi-fracture-cavity reservoir, and the horizontal well layout pattern for bedding multi-fracture-cavity reservoirs is established; If the morphological characteristics of the seismic response are "beaded" responses, multiple "beaded" responses are continuously distributed in the horizontal and vertical directions, which is reflected in the "beaded" oblique distribution mode. This is a multi-layer multi-fracture-cavity reservoir, and a multi-layer multi-fracture-cavity reservoir high-angle well layout mode is established.

[0039] If the morphological characteristics of the seismic response are "beaded" and "sheet-like" responses, which are continuous in the horizontal direction but discontinuous in the vertical direction, this type of reservoir is a bedding-type pore-vuggy + fracture-cavity reservoir. In this case, a horizontal well layout pattern for bedding-type pore-vuggy + fracture-cavity reservoirs is established.

[0040] If the morphological characteristics of the seismic response are "sheet-like" response or weak reflection response, which is continuous in the horizontal direction but discontinuous in the vertical direction, this is a fracture-pore type reservoir with bedding development. In this case, a horizontal well layout pattern for the fracture-pore type reservoir with bedding development should be established.

[0041] S4. According to different well layout modes, refer to the instructions. Figure 2 , establish the corresponding well trajectory design method. Specifically: If it is an isolated large-scale fracture-cavity reservoir vertical well layout mode, deploy vertical wells and control the well trajectory to drill from the middle of the reservoir. When leakage or emptying occurs, force drilling is performed to maximize the oil leakage area.

[0042] If the horizontal well layout mode is a multi-fracture-cavity reservoir along the layer, the horizontal well is deployed and the trajectory of the horizontal well is controlled to pass within 10m above the top of the reservoir to avoid serious leakage or emptying during drilling. After acidizing or fracturing, multiple fractures and caves can be connected to achieve high production of horizontal wells.

[0043] If the well layout pattern is a multi-layer, multi-fracture-cavity reservoir with a high-angle well, then a high-angle well should be deployed, and the horizontal well trajectory should be controlled to pass obliquely within 10m above the top of each fracture-cavity body to avoid serious leakage or emptying during drilling. After acidizing or fracturing, multiple fracture-cavity bodies can be connected to achieve high production of high-angle wells.

[0044] If the horizontal well layout pattern is a layer-parallel hole-type + fracture-cavity reservoir, deploy horizontal wells and control the trajectory of the horizontal wells to drill from the middle of the hole-type reservoir with a seismic "sheet" response, and drill into the fracture-cavity reservoir with a "beaded" response at the end. When drilling into the fracture-cavity reservoir, force drilling is performed when there is leakage or emptying to maximize the leakage area.

[0045] If the horizontal well layout pattern is a bedding fracture-hole reservoir, then deploy the horizontal wells and control the trajectory of the horizontal wells to drill from the middle of the fracture-hole reservoir with a seismic "sheet" response to increase the reservoir drilling rate of the horizontal wells.

[0046] This embodiment fully considers the response characteristics of fracture-cavity carbonate reservoirs in earthquakes and predicts the location, scale and distribution of fracture-cavity bodies. On this basis, a combination mode of seismic response of fracture-cavity reservoirs and 5 well layout modes are established, which not only achieves geological goals, but also greatly reduces the occurrence of engineering complexities, and significantly improves the success rate of drilling. This method has been widely used in fracture-cavity carbonate condensate gas reservoirs in Tazhong, fracture-cavity carbonate gas reservoirs in Dengying Formation of Penglai gas field in Sichuan, and subsalt carbonate gas reservoirs on the right bank of the Amu Darya River in Turkmenistan, which improves the reservoir drilling rate in these blocks, achieves high and stable production of single wells, and can save a lot of money.

[0047] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the present invention without creative mental labor, which all fall within the scope of protection of the present invention.

Claims

1. A method for designing well trajectories in fracture-cavity carbonate reservoirs based on seismic response characteristics, characterized in that: The following steps are involved: S1. Select the target area; S2. Determine the morphological characteristics of earthquake responses and the combination of various earthquake responses; S3. Establish different well layout patterns according to the morphological characteristics and combination methods of seismic response; S4. Establish corresponding well trajectory design methods according to different well layout patterns.

2. The method for designing well trajectories in fracture-cavity carbonate reservoirs based on seismic response characteristics according to claim 1, characterized in that: Step S1 refers to: selecting a target area according to the plane amplitude attributes of the seismic data.

3. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 2 is characterized by: Step S1 specifically refers to: selecting a strong amplitude development area as a target area according to the plane amplitude attribute of the seismic data.

4. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 1 or 3, characterized in that: The morphological characteristics of the seismic response in step S2 include "beaded" response, "sheet" response and weak reflection response.

5. The method for designing well trajectories in fracture-cavity carbonate reservoirs based on seismic response characteristics according to claim 4, characterized in that: The morphological characteristics of the seismic response are obtained by classifying the strong amplitude reflections on the seismic section of the target area according to different morphologies.

6. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 4, characterized in that: Determining the combination mode of various earthquake responses specifically refers to: analyzing the connectivity between the various fracture-caves and the internal structure of the fracture-caves according to the characteristics of different karst fracture-caves in different karst areas, spatially grouping the fracture-caves in three-dimensional space, and establishing the longitudinal and transverse combination modes of various earthquake responses.

7. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 6, characterized in that: The well layout patterns include vertical well layout patterns for isolated large fracture-cavity reservoirs, horizontal well layout patterns for in-bedding multi-fracture-cavity reservoirs, high-angle well layout patterns for multi-layer multi-fracture-cavity reservoirs, horizontal well layout patterns for in-bedding hole-cavity + fracture-cavity reservoirs, and horizontal well layout patterns for in-bedding fracture-hole reservoirs.

8. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 7, characterized in that: Step S3 specifically refers to: If the seismic response is characterized by a "beaded" response and is discontinuous in the horizontal and vertical directions, then a vertical well layout pattern for isolated large fracture-cavity reservoirs is established; If the morphological characteristics of the seismic response are "beaded" responses, with multiple "beaded" responses continuous in the horizontal direction and discontinuous in the vertical direction, then the horizontal well layout pattern for the multi-fracture-cavity reservoir in the bedding layer is established; If the morphological characteristics of the seismic response are "beaded" responses, and multiple "beaded" responses are continuously distributed in the lateral and vertical directions, then a high-angle well layout pattern for multi-layer, multi-fracture-cavity reservoirs is established; If the morphological characteristics of the seismic response are "beaded" and "sheet-like" responses, which are continuous in the horizontal direction but discontinuous in the vertical direction, then the horizontal well layout pattern of the layer-parallel hole-type + fracture-type reservoir is established; If the morphological characteristics of the seismic response are "sheet-like" response or weak reflection response, which is continuous in the horizontal direction but discontinuous in the vertical direction, then a horizontal well layout pattern for the bedding fracture-hole type reservoir is established.

9. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 8, characterized in that: Step S4 specifically refers to: If it is an isolated large fracture-cavity reservoir vertical well layout mode, deploy vertical wells and control the well trajectory to drill from the middle of the reservoir, and force drilling when leakage or emptying occurs; If the horizontal well layout mode is a multi-fracture-cavity reservoir along the layer, deploy horizontal wells and control the horizontal well trajectory to pass within 10m above the top of the reservoir; If the well layout mode is a multi-layer, multi-fracture-cavity reservoir with a high-angle well, a high-angle well is deployed, and the horizontal well trajectory is controlled to cross obliquely within 10m above the top of each fracture-cavity body; If the horizontal well layout mode is for the bedding-type pore-vuggy + fracture-cavity reservoir, then deploy the horizontal wells and control the horizontal well trajectory to drill from the middle of the pore-vuggy reservoir with a seismic "sheet" response, and drill into the fracture-cavity reservoir with a "beaded" response at the end. When drilling into the fracture-cavity reservoir, force drilling when leakage or emptying occurs; If the horizontal well layout mode is a bedding fracture-hole reservoir, then deploy the horizontal wells and control the trajectory of the horizontal wells to drill from the middle of the fracture-hole reservoir with a "sheet-like" seismic response.

10. The method for designing well trajectory of fracture-cavity carbonate reservoir based on seismic response characteristics according to claim 9, characterized in that: When it is a horizontal well layout pattern for a bedding multi-fracture-cavity reservoir or a high-angle well layout pattern for a multi-layer multi-fracture-cavity reservoir, multiple fracture-cavity bodies can be connected after acidizing or fracturing.

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