Differentiated straight-flat combined three-dimensional energy complementing well pattern design method for ultra-low permeability reservoir

Abstract

The invention discloses an ultra-low permeability reservoir differentiated straight-flat combined three-dimensional energy complementing well pattern design method which comprises the following steps: deploying horizontal wells in an oil reservoir in a layered manner, so that planes of the horizontal wells in the upper layer and the lower layer are staggered and longitudinally superposed, and the lengths, the row pitches and the orientations of the horizontal wells are similar or consistent; designing a first ground platform and a second ground platform which are oppositely arranged, and enabling a point A and a point B of the upper-layer horizontal well and a point B and a point A of the lower-layer horizontal well to be on the same side respectively; respectively deploying a first injection vertical well and a second injection vertical well at the positions in the direction of the outer side of the central axis where the points B of the two adjacent upper-layer horizontal wells and the points B of the two adjacent lower-layer horizontal wells are connected; perforations of the first injection vertical well and the second injection vertical well are arranged at points B of the upper-layer horizontal well and the lower-layer horizontal well respectively, and perforations are arranged near points A of the upper-layer horizontal well and the lower-layer horizontal well; the first injection vertical well and the second injection vertical well adopt a layered injection mode, and the point B and the point A of each horizontal well are respectively designed to increase the injection amount and reduce the injection amount. According to the invention, effective utilization of the reservoir is realized, and three-dimensional energy supplementation is realized.

Description

Technical Field

[0001] The present invention relates to a vertical well energy supplement scheme and a well pattern structure design method suitable for ultra-low permeability oil reservoirs developed by horizontal wells, and more specifically, to a differentiated vertical and horizontal combination three-dimensional energy supplement well pattern design method for ultra-low permeability oil reservoirs. Background Art

[0002] In recent years, low-permeability and ultra-low-permeability reservoirs have gradually occupied an important position in the newly-proven reserves, and the production share of this type of reservoir has been increasing year by year. Horizontal well volume fracturing has been proven to be one of the important means to effectively develop this type of reservoir. As the largest block in the Liaohe peripheral area with newly-added reserves in recent years, the He 21 block in Kailu area has reservoir geological characteristics that meet the ultra-low permeability limit. After preliminary exploration and evaluation, horizontal well volume fracturing development has achieved more significant results than vertical well development. After entering the development stage, favorable areas are concentrated according to the development characteristics of the reservoirs. In areas where a set of horizontal wells cannot be fully utilized, two layers of horizontal wells with staggered planes and vertically stacked layers are deployed for stratified utilization and development. This three-dimensional well network has achieved remarkable results, with a high degree of reserve utilization, high single-well production, and fast oil production.

[0003] However, with the high-liquid production of horizontal wells relying on natural energy, how to replenish the formation energy in a large scale and effectively has become a difficult point in the development of ultra-low permeability reservoirs. Artificial energy replenishment is firstly restricted by the complex fracture network formed by volume fracturing. The conventional general injection method is very likely to produce high-speed seepage of the displacement phase along the secondary fractures, and it is impossible to form a considerable swept volume; secondly, due to the pressure difference of the seepage field in the horizontal well section of the horizontal well network, it is also easy to cause the displacement medium to quickly gather near the horizontal well point A and be produced; finally, due to the ultra-low permeability reservoir itself, whether the injected medium can establish an effective displacement system is also a key consideration in reservoir engineering design.

[0004] Therefore, the prior art needs to be improved. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for designing a differentiated straight-horizontal combination three-dimensional energy replenishment well network for ultra-low permeability reservoirs. On the one hand, the present invention can achieve effective reservoir utilization: in oil reservoirs that cannot be fully utilized by a set of horizontal wells, effective utilization is achieved by using rationally layered deployment of horizontal wells; on the other hand, three-dimensional energy replenishment can be achieved: focusing on solving the problem of how to effectively replenish formation energy during the layered development of horizontal wells, while achieving three-dimensional energy replenishment and minimizing the crossflow phenomenon caused by pressure field distribution and secondary fractures. The present invention can ultimately achieve relatively long-term stable production of horizontal wells, while achieving the efficient utilization and development of this type of oil reservoir.

[0006] The technical solution adopted by the present invention is as follows:

[0007] According to one aspect of the present invention, a method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for an ultra-low permeability reservoir is provided, comprising the following steps:

[0008] 1) Horizontal wells are deployed in layers in the reservoir, and the upper horizontal wells and the lower horizontal wells are arranged in a "plane staggered and vertically stacked" relationship and their lengths, row spacings and azimuth parameters are kept similar or consistent, wherein the two ends of the horizontal sections of the upper horizontal wells and the lower horizontal wells are designed as points A and B;

[0009] 2) Designing the first and second ground platforms opposite to each other according to the layer where the horizontal well is located, and making point A of the upper horizontal well and point B of the lower horizontal well on the same side, and point B of the upper horizontal well and point A of the lower horizontal well on the same side to ensure that the upper horizontal well and the lower horizontal well are drilled in opposite directions;

[0010] 3) deploying the first vertical injection well at a reasonable position outside the central axis connecting point B of two adjacent upper horizontal wells;

[0011] 4) deploying a second vertical injection well at a reasonable position outside the central axis connecting point B of two adjacent lower horizontal wells;

[0012] 5) deploying perforations of the first vertical injection well at point B of the upper horizontal well in the layer, and deploying perforations of the first vertical injection well near point A of the lower horizontal well;

[0013] 6) deploying perforations of the second vertical injection well at point B of the lower horizontal well in the same layer, and deploying perforations of the second vertical injection well near point A of the upper horizontal well;

[0014] 7) The first vertical injection well and the second vertical injection well adopt a layered injection method, and the point B of the upper horizontal well and the point B of the lower horizontal well are designed to increase the injection volume, and the point A of the upper horizontal well and the point A of the lower horizontal well are designed to reduce the injection volume.

[0015] In one embodiment of the present invention, in step 1), the oil reservoir has economic feasibility and geological necessity for layered deployment.

[0016] In one embodiment of the present invention, in step 1), when horizontal wells are deployed in layers in the reservoir, the length, row spacing and orientation of the horizontal wells are determined according to the actual conditions of the reservoir and the occurrence of the fractures.

[0017] In one embodiment of the present invention, when deploying horizontal wells, the lengths of the various horizontal wells are kept equal.

[0018] In one embodiment of the present invention, when deploying a horizontal well, the length of the horizontal well is controlled to be 500-700 m.

[0019] In one embodiment of the present invention, when deploying horizontal wells, the spacing of the horizontal wells is determined based on the development of faults and the length of fractures.

[0020] In one embodiment of the present invention, when deploying horizontal wells, the row spacing of the horizontal wells is smaller than the length of the microseismic monitoring fracture.

[0021] In one embodiment of the present invention, when deploying a horizontal well, the horizontal well avoids the fault by more than 100 m.

[0022] In one embodiment of the present invention, when deploying horizontal wells, the row spacing of the horizontal wells is controlled to be 230-280 m.

[0023] In one embodiment of the present invention, when deploying a horizontal well, the deployment orientation of the horizontal well is at an angle of 60°-90° to the principal stress direction.

[0024] In one embodiment of the present invention, in step 2), the first ground platform forms an upper local horizontal well network with the upper horizontal wells through a first pre-target displacement, and the second ground platform forms a lower local horizontal well network with the lower horizontal wells through a second pre-target displacement.

[0025] In one embodiment of the present invention, the upper local horizontal well network is combined with the lower local horizontal well network to form a three-dimensional horizontal well network.

[0026] In one embodiment of the present invention, in steps 3) and 4), the first vertical injection well is completely identical to the second vertical injection well.

[0027] In one embodiment of the present invention, the injection media of the first vertical injection well and the second vertical injection well include water, gas, foam, polymer and gel.

[0028] In one embodiment of the present invention, the first ground platform deploys the second vertical injection well through a third pre-target displacement, and the second ground platform deploys the first vertical injection well through a fourth pre-target displacement.

[0029] In one embodiment of the present invention, in steps 3) and 4), a reasonable position is determined based on overall factors of the reservoir and fracturing.

[0030] In one embodiment of the present invention, the injection-production well spacing is designed to be 100-120m.

[0031] In one embodiment of the present invention, in steps 5) and 6), perforation is performed without fracturing or in a manner of controlling the scale of fracturing.

[0032] In one embodiment of the present invention, in step 7), the corresponding injection volume is adjusted according to the reservoir development characteristics and the actual injection-production well spacing, and then the corresponding injection volume is dynamically adjusted according to the production well effectiveness and water breakthrough characteristics.

[0033] According to another aspect of the present invention, a differentiated straight-flat combination three-dimensional energy compensation well network structure for ultra-low permeability reservoirs is provided, wherein the structure is designed by the differentiated straight-flat combination three-dimensional energy compensation well network design method for ultra-low permeability reservoirs as described above.

[0034] By adopting the above technical solution, the present invention has at least the following beneficial effects:

[0035] (1) The present invention greatly improves the utilization of reserves and reduces the loss of recoverable reserves. It is not necessary to reserve space for injection wells in the lower part of the reservoir, and the same-layer injection and production are adopted to realize the overall utilization of the reservoir.

[0036] (2) The present invention improves the injection efficiency of the injection well to a great extent, and avoids the phenomenon of cross-flow caused by the pressure field distribution near the horizontal well section and artificial fractures as much as possible through the optimization and reasonable application of the well network structure.

[0037] (3) The present invention improves the production efficiency of oil wells and theoretically achieves full-time production of oil wells. There is no reduction in the production time of production wells due to asynchronous injection and production, water injection throughput and other measures, which reasonably improves the oil production speed and production efficiency of the oil reservoir. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 The schematic diagram of the process of the method for designing a differentiated straight-flat combined three-dimensional energy replenishment well pattern for an ultra-low permeability reservoir provided by the present invention is shown;

[0040] Figure 2 is to use Figure 1 A top view of the differentiated straight-flat combined three-dimensional energy replenishment well network structure designed by the method;

[0041] Figure 3 is to use Figure 1 Side view of the differentiated straight-flat combined three-dimensional energy replenishment well pattern structure designed by the method;

[0042] Figure 4 is to use Figure 1 A three-dimensional diagram of the differentiated straight-flat combined three-dimensional energy replenishment well network structure designed by the method.

[0043] Reference numerals list

[0044] 1 upper horizontal well, 2 lower horizontal well, 3 first vertical injection well, 4 second vertical injection well, 11 first pre-target displacement, 12 upper layer system reference plane, 21 second pre-target displacement, 22 lower layer system reference plane, 31 third pre-target displacement, 32 upper layer system injection streamline, 33 lower layer system injection streamline, 34 perforation, 35 fourth pre-target displacement, 41 first ground platform, 42 second ground platform. DETAILED DESCRIPTION

[0045] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0046] like Figure 1-4 As shown, the present invention provides a method for designing a differentiated straight-flat combined three-dimensional energy-replenishing well pattern for an ultra-low permeability reservoir. The steps of the method are as follows:

[0047] Step S101: deploy horizontal wells in layers in the reservoir, and determine reasonable length, row spacing, and orientation of the horizontal wells according to factors such as the actual conditions of the reservoir and the occurrence of fractures. The upper and lower horizontal wells 1 and 2 should follow the relationship of "plane staggered and vertically stacked" to keep parameters such as length, row spacing, and orientation similar or consistent. The two ends of the horizontal section of the upper horizontal well 1 and the lower horizontal well 2 are designed as point A and point B.

[0048] Step S102: Design two oppositely arranged first and second ground platforms 41, 42 according to the stratum where the horizontal well is located, so that point A of the upper horizontal well 1 and point B of the lower horizontal well 2 are on the same side and point B of the upper horizontal well 1 and point A of the lower horizontal well 2 are on the same side, that is, the drilling directions of the upper and lower horizontal wells 1, 2 are opposite.

[0049] Step S103: deploying a first vertical injection well 3 at a reasonable position outside the central axis connecting point B of two adjacent upper horizontal wells 1.

[0050] Step S104: deploy a second vertical injection well 4 at a reasonable position outside the central axis connecting point B of two adjacent lower-layer horizontal wells 2.

[0051] Step S105: deploy the first vertical injection well 3 at point B of the upper horizontal well 1 with perforations 34 in the local layer, and inject without fracturing or with controlled fracturing scale. The first vertical injection well 3 deploys perforations 34 near point A of the lower horizontal well 2, and inject without fracturing or with controlled fracturing scale.

[0052] Step S106: deploy a second vertical injection well 4 at point B of the lower horizontal well 2, perforate 34 in the local layer, and inject without fracturing or by controlling the scale of fracturing. The second vertical injection well 4 deploys perforations 34 near point A of the upper horizontal well 1, and injects without fracturing or by controlling the scale of fracturing.

[0053] Step S107: The first and second vertical injection wells 3 and 4 both adopt a layered injection method, with a larger injection scale designed at point B of the upper horizontal well 1 and point B of the lower horizontal well 2, and a smaller injection scale designed at point A of the upper horizontal well and point A of the lower horizontal well 2.

[0054] In the above method of the present invention, the injection medium of the first and second vertical injection wells 3, 4 can be water, gas, foam, polymer, gel, etc.

[0055] In the above method of the present invention, the oil reservoir should have the economic feasibility of layered deployment and the geological necessity of layered deployment; the length of the oil well mainly considers the rationality of the injection and production well network. Since the vertical well injection method is adopted, the horizontal well section should not be too long. The short horizontal well "five-point method" well network is designed. Combined with the mine experience, the reasonable length in the low permeability reservoir is 500-700m; the row spacing of the oil wells mainly refers to the fault development and the length of the hydraulic fracture. The row spacing should be less than the microseismic monitoring fracture length. If the actual fracture monitoring in the mine is about 200m, the reasonable row spacing is designed to be 230-280m. At the same time, the horizontal wells should be deployed to avoid faults for more than 100m; the orientation of the oil wells mainly refers to the development of faults and the direction of hydraulic fracture development. The deployment orientation of the oil wells should be 60°-90° with the main stress direction to avoid rapid advancement of the injection phase, increase the swept volume, and optimize the transformation volume of the oil wells after hydraulic fracturing.

[0056] In the above method of the present invention, two oppositely arranged first ground platforms 41 and second ground platforms 42 are designed for the stratum where the horizontal well is located, the upper horizontal well 1 is drilled entirely with the first ground platform 41, and the lower horizontal well 2 is drilled entirely with the opposite second ground platform 42, and the upper horizontal well 1 and the lower horizontal well 2 have the same orientation and opposite drilling directions.

[0057] In the above method of the present invention, the reasonable position of the outer side of the central axis connecting point B of each horizontal well should consider the overall factors of the reservoir and fracturing, that is, the fracture width of each horizontal well should not affect the drilling position of the vertical well, and the recommended injection and production well spacing is 100-120m.

[0058] In the above method of the present invention, the first vertical injection well 3 and the second vertical injection well 4 are injected by perforation 34 in both the upper and lower layers. The pressure difference between the reservoir characteristics and the seepage field of the underground horizontal well section should be considered. Appropriate fracturing measures are taken near point B of the upper horizontal well 1 and point B of the lower horizontal well 2 to reduce the injection difficulty and increase the injection amount. The original formation porosity and permeability characteristics are maintained as much as possible near point A of the upper horizontal well 1 and point A of the lower horizontal well 2 to reduce the injection amount and slow down the advance.

[0059] More specifically, when the above method is implemented, Figure 2-4 As shown, the present invention provides a method for designing a differentiated vertical and horizontal combined three-dimensional energy supplement well pattern for ultra-low permeability reservoirs. While achieving effective reservoir utilization, the formation energy is effectively supplemented to achieve long-term stable production of horizontal wells, which mainly includes the following steps:

[0060] (1) Horizontal wells are deployed in layers in the reservoir, wherein an upper horizontal well 1 and a lower horizontal well 2 are deployed. The upper and lower horizontal wells 1 and 2 are arranged alternately in plane projection, and the horizontal well trajectories are parallel, the orientations are consistent, and the horizontal well section lengths are consistent or close. For details, see Figure 2 As shown. In this step, according to the actual situation of the reservoir, the deployment of a layer of horizontal wells cannot rely on volume fracturing to form a large-scale fracture network to connect the two sets of reservoirs. Therefore, it is necessary to deploy horizontal wells in layers in geology. After economic calculation, the internal rate of return of the layered deployment of horizontal wells is 16.8%, which is economically feasible for layered deployment of horizontal wells. Ideally, the length of each horizontal well should be equal. In the actual deployment process, the length of each horizontal well should be appropriately adjusted according to the development of the oil layer. However, the length difference of horizontal wells in the same area should not be too large. The length of the horizontal well should be controlled within 600m. The horizontal well spacing is based on the development of faults and the length of the fractures. In theory, the spacing should be less than the length of the microseismic monitoring fracture to maximize the fracturing transformation volume. At the same time, the horizontal wells should avoid faults for more than 100m. Therefore, the reasonable spacing of horizontal wells is determined to be 250m based on the above factors. The orientation of the deployed horizontal wells mainly refers to the development of faults and the direction of the fractures. The orientation of the production wells should be preferably 60° with the direction of the principal stress. At the same time, the horizontal wells are deployed along the direction of the fault development to maximize the well network control.

[0061] (2) According to the stratum where the horizontal well is located, two opposing first ground platforms 41 and second ground platforms 42 are designed, referring to Figure 2 As shown, the first ground platform 41 forms an upper local horizontal well network with the upper horizontal well 1 through the first pre-target displacement 11; the second ground platform 42 forms a lower local horizontal well network with the lower horizontal well 2 through the second pre-target displacement 21, and the upper and lower well networks are combined to form a three-dimensional horizontal well network.

[0062] (3)Reference Figure 2 and 4As shown, at a reasonable position outside the central axis line of point B of two adjacent upper horizontal wells 1, the second platform 42 in the lower layer (the structure at the lower layer reference plane 22) is designed by the fourth target front displacement 35 to form a local injection and production well network. The deployment position should take into account the overall factors of the reservoir and fracturing, and the injection and production well spacing is designed to be 100m.

[0063] (4) At a reasonable position outside the central axis line connecting point B of two adjacent lower horizontal wells 2, the first platform 41 in the upper layer system (the structure at the upper layer system reference plane 12) is designed through the third pre-target displacement 31 to design the second injection vertical well 4 to form a local injection and production well network. The vertical wells and horizontal wells form a three-dimensional injection and production well network, in which the first injection vertical well 3 and the second injection vertical well 4 are exactly the same.

[0064] (5)Reference Figure 2-3 As shown, the first vertical injection well 3 on the first platform 41 is deployed with perforations 34. The perforations 34 are placed at point B corresponding to the upper horizontal well 1 without fracturing or with a controlled fracturing scale. The perforations 34 are placed at point A corresponding to the lower horizontal well 2 without fracturing or with a controlled fracturing scale.

[0065] (6)Reference Figure 2-3 As shown, the second vertical injection well 4 on the second platform 42 is deployed with perforations 34. The perforations 34 are placed at point B corresponding to the lower horizontal well 2 without fracturing or with a controlled fracturing scale. The perforations 34 are placed at point A corresponding to the upper horizontal well 1 without fracturing or with a controlled fracturing scale.

[0066] (7) Figure 2-4 As shown, the first vertical injection well 3 and the second vertical injection well 4 both adopt the layered injection method, wherein the perforation 34 of the second vertical injection well 4 in the upper layer corresponds to the injection streamline 32, and the injection volume should be appropriately reduced at point A of the upper horizontal well 1, and the injection volume can be relatively increased at point B of the lower horizontal well 2; the perforation 34 of the first vertical injection well 3 in the lower layer corresponds to the injection streamline 33, and the injection volume should be appropriately reduced at point A of the lower horizontal well 2, and the injection volume can be relatively increased at point B of the upper horizontal well 1. The injection volume of the perforation 34 of each injection well should follow the principle of "less injection near point A, more injection near point B", and the injection-production ratio should be maintained at 1:1 in general. The designed injection volume can be appropriately adjusted according to the reservoir development characteristics and the actual injection-production well spacing, and then the injection volume can be dynamically adjusted according to the production well effect and water breakthrough characteristics.

[0067] Therefore, through the above-mentioned embodiments of the present invention, the present invention realizes effective reservoir utilization on the one hand: in an oil reservoir that cannot be fully utilized by a set of horizontal wells, effective utilization is achieved by utilizing reasonable layered deployment of horizontal wells; and on the other hand, three-dimensional energy replenishment is achieved: focusing on solving the problem of how to effectively replenish formation energy during the layered development of horizontal wells, while achieving three-dimensional energy replenishment, the crossflow phenomenon caused by pressure field distribution and secondary fractures is minimized.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of implementation of the present invention. If the present invention is modified or replaced by equivalents without departing from the spirit and scope of the present invention, it should be covered by the protection scope of the claims of the present invention.

Claims

1. A method for designing a differentiated straight-flat combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs, characterized in that: The following steps are involved: 1) Horizontal wells are deployed in layers in the reservoir, and the upper horizontal wells and the lower horizontal wells are arranged in a "plane staggered and vertically stacked" relationship and their lengths, row spacings and azimuth parameters are kept similar or consistent, wherein the two ends of the horizontal sections of the upper horizontal wells and the lower horizontal wells are designed as points A and B; 2) Designing the first and second ground platforms opposite to each other according to the layer where the horizontal well is located, and making point A of the upper horizontal well and point B of the lower horizontal well on the same side, and point B of the upper horizontal well and point A of the lower horizontal well on the same side to ensure that the upper horizontal well and the lower horizontal well are drilled in opposite directions; 3) deploying the first vertical injection well at a reasonable position outside the central axis connecting point B of two adjacent upper horizontal wells; 4) deploying a second vertical injection well at a reasonable position outside the central axis connecting point B of two adjacent lower horizontal wells; 5) deploying perforations of the first vertical injection well at point B of the upper horizontal well in the layer, and deploying perforations of the first vertical injection well near point A of the lower horizontal well; 6) deploying perforations of the second vertical injection well at point B of the lower horizontal well in the same layer, and deploying perforations of the second vertical injection well near point A of the upper horizontal well; 7) The first vertical injection well and the second vertical injection well adopt a layered injection method, and the point B of the upper horizontal well and the point B of the lower horizontal well are designed to increase the injection volume, and the point A of the upper horizontal well and the point A of the lower horizontal well are designed to reduce the injection volume.

2. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1 is characterized in that: In step 1), the oil reservoir has economic feasibility and geological necessity for layered deployment.

3. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 2 is characterized in that: In step 1), when horizontal wells are deployed in layers in the reservoir, the length, row spacing and orientation of the horizontal wells are determined according to the actual conditions of the reservoir and the occurrence of the fractures.

4. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1 is characterized in that: When deploying horizontal wells, the lengths of the various horizontal wells are kept equal.

5. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1 is characterized in that: When deploying horizontal wells, the length of the horizontal wells is controlled at 500-700m.

6. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1 is characterized in that: When deploying horizontal wells, the spacing of horizontal wells is determined based on the development of faults and the length of fractures.

7. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 6 is characterized in that: When deploying horizontal wells, the spacing between horizontal wells is smaller than the length of the microseismic monitoring fracture.

8. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 7 is characterized in that: When deploying horizontal wells, the horizontal wells should avoid faults by more than 100m.

9. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 8 is characterized in that: When deploying horizontal wells, the row spacing of horizontal wells is controlled at 230-280m.

10. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: When deploying horizontal wells, the deployment orientation of the horizontal wells is at an angle of 60°-90° to the principal stress direction.

11. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: In the step 2), the first ground platform forms an upper local horizontal well pattern with the upper horizontal wells through a first pre-target displacement, and the second ground platform forms a lower local horizontal well pattern with the lower horizontal wells through a second pre-target displacement.

12. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 11, characterized in that: The upper local horizontal well network is combined with the lower local horizontal well network to form a three-dimensional horizontal well network.

13. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: In steps 3) and 4), the first vertical injection well is exactly the same as the second vertical injection well.

14. The method for designing a differentiated straight-horizontal combined three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 13, characterized in that: The injection media of the first vertical injection well and the second vertical injection well include water, gas, foam, polymer and gel.

15. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 14, characterized in that: The first ground platform deploys the second vertical injection well through the third target front displacement, and the second ground platform deploys the first vertical injection well through the fourth target front displacement.

16. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: In the steps 3) and 4), the appropriate positions are determined based on the overall factors of the reservoir and fracturing.

17. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 16, characterized in that: The distance between injection and production wells is designed to be 100-120m.

18. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: In the steps 5) and 6), perforation is performed without fracturing or in a manner of controlling the scale of fracturing.

19. The method for designing a differentiated straight-horizontal combination three-dimensional energy-replenishing well pattern for ultra-low permeability reservoirs according to claim 1, characterized in that: In step 7), the corresponding injection volume is adjusted according to the reservoir development characteristics and the actual injection-production well spacing, and then the corresponding injection volume is dynamically adjusted according to the production well effectiveness and water breakthrough characteristics.

20. A differentiated straight-flat combination three-dimensional energy-replenishing well pattern structure for ultra-low permeability reservoirs, characterized in that: The well pattern is designed by the method for designing a differentiated straight-flat combined three-dimensional energy replenishment well pattern for ultra-low permeability reservoirs as described in any one of claims 1 to 19.

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