Shale oil horizontal well group energy complementing and crack expanding synergistic fracturing method

Abstract

The invention discloses a shale oil horizontal well group energy supplementing and crack expanding collaborative fracturing method. The method comprises the following steps: A, modeling, simulating and optimizing CO2 injection parameters of a production well, and injecting CO2 into the production well for pressurization and energy supplementation in advance; b, fracturing construction is conducted on a new well of the shale oil horizontal well set, and fracturing is conducted from outside to inside in sequence; c, differentiated fracturing is carried out on the horizontal fracturing section of the single well, three areas are divided along the horizontal section, and perforation, segmentation and scale parameters of all the areas are differentially designed; and D, well soaking is conducted after fracturing of each horizontal well in the shale oil horizontal well group is completed, and well opening and open flow production are conducted when well mouth pressure is diffused to be stable. The method has the advantages that the energy utilization rate is increased, the transformation efficiency is improved, well group energy supplementing and crack expanding collaborative fracturing is completed, the optimization problem of a production well and a to-be-fractured well under the horizontal well network condition is solved, the horizontal well group transformation effect and the reservoir utilization degree maximization are achieved, the well group recovery efficiency is improved, and the potential of oil reservoir yield increasing is fully released.

Description

Technical Field

[0001] The invention relates to a hydraulic fracturing technology for oil and gas field exploration and development, and in particular to a shale oil horizontal well group energy supplementation and seam expansion coordinated fracturing method. Background Art

[0002] The shale oil reservoir in the structural stable area of ​​the Fu 2nd Member in the Qintong Sag in the Subei Basin has developed laminations, is relatively homogeneous, 200-480 meters thick, and has low permeability. It is necessary to use large-scale fracturing to improve the permeability of the reservoir and form a hydraulic fracture network connected to the horizontal wellbore, so that the crude oil in the low-permeability reservoir can flow more easily to the wellbore to provide production capacity; in the development process, priority is given to the exploration and deployment of an exploration and evaluation well. After a period of production to achieve a breakthrough in production capacity, multiple horizontal wells are deployed for platform well group development.

[0003] During the fracturing process of the well group, the formation pressure deficit caused by the production of the production wells causes a significant change in the original stress field of the reservoir. The fracture system composed of the artificial fractures and natural fractures of the production wells and the wells to be fractured induces interference between wells. There are different levels of communication responses, which affect the fracturing effect of the wells to be fractured and damage the production capacity of the well network. After the production wells resume production, the wellhead pressure of the fractured wells drops significantly, the production wells accumulate fluid seriously, and the water content is high. In severe cases, the production wells will bleed sand, the casing will be deformed and scrapped, and the production capacity of the production wells will be restricted. At present, the conventional fracturing process of horizontal wells has similar lengths of each segment and similar construction scale of each segment. The difficulty of adding sand and the construction pressure decrease from high to low from the toe end to the root end of the horizontal well. The construction process mode shows a certain degree of singleness. At present, there is a lack of systematic scientific improvement methods. It is urgent to achieve a leap and development in technology through innovative means. Summary of the invention

[0004] In order to solve the problem of inter-well interference induced by well group fracturing, the technical problem actually to be solved by the present invention is to provide a shale oil horizontal well group energy-enhancing and seam-expanding collaborative fracturing method that can simultaneously ensure the coordinated and efficient transformation between wells in the horizontal well group and fully utilize the well network reserves.

[0005] In order to solve the above technical problems, the shale oil horizontal well group energy supplementation and seam expansion coordinated fracturing method of the present invention comprises the following steps: A: Modeling and simulation to optimize the CO2 injection parameters of production wells in shale oil horizontal well groups, and inject CO2 to boost pressure and replenish energy in production wells in advance; In this step, a three-dimensional finite element geomechanical model of a shale oil horizontal well group and a three-dimensional shale gas seepage model are established. Taking the three-dimensional pore pressure change as the boundary condition, the changes in the ground stress at different times after the production well pressure is calculated, and finally the pore pressure and ground stress range of the production well for long-term exploitation are determined; then the CO2 injection is simulated to increase the pressure and replenish the energy in the production area, the CO2 injection amount is optimally determined, and the CO2 injection is implemented in the production well to increase the formation pressure in the production well fracture network and the well group area; B: Conduct fracturing construction of new wells in shale oil horizontal well groups, fracturing from outside to inside; In this step, the outermost horizontal well in the fracturing shale oil horizontal well group is preferentially selected, and then fracturing is performed one by one from the outside to the inside; the wellhead fracturing processes of the horizontal wells on both sides are connected, and the process conversion is realized through the diversion manifold, and a set of fracturing vehicles is shared to perform uninterrupted alternating zipper fracturing of the two wells; C: Carry out differentiated fracturing in the horizontal fracturing section of a single well, divide the horizontal section into three areas, and design the perforation, segmentation, and scale parameters of each area differently; use a low-viscosity fracturing fluid system, large displacement, and large fluid volume to create a complex fracture network; D: After completing the fracturing of each horizontal well in the shale oil horizontal well group, the well is shut down and when the wellhead pressure diffuses to a stable state, the well is opened for production.

[0006] In the step A, a small-layer structural stratum matrix model is established in the well group area, and a matrix attribute model is established by using the seismic inversion porosity body and saturation body as trend constraints and applying the sequential Gaussian method; Establish a fracture model. Based on seismic data and ant body attributes, clarify the overall distribution of fractures in the well group area. Combined with the well logging fracture development intensity, establish large-scale, medium-scale and small-scale DFN fracture models. Establish a geostress model, using the well group brittleness index, rock mechanics characteristic parameters, and the fracture distribution and geostress orientation parameters obtained by imaging logging, and use finite element simulation on the basis of the three-dimensional geological model to construct a geostress field model; A reservoir-fluid-rock model is established. Based on the monitoring data of production well fracturing, the transformation SRV, and the fracture morphology, the damage and rupture of the reservoir, matrix filtration, and the interactive deformation of rocks and fractures are taken into consideration. A production well fracturing network expansion model is established, and the dynamic evolution of the in-situ stress after production well fracturing is evaluated to determine the pore pressure and in-situ stress range of the production well. The zoned phase permeability is used to characterize the differences in physical properties of different reservoirs and flow media, and an equivalent permeability field of fracture distribution is established.

[0007] In step A, the CO2 injection scale is optimized, different gas injection volumes are simulated, and the injection volume with a significant increase in oil production is preferred, and CO2 injection is carried out in advance in the production well. After the injection scale is completed, the fracturing construction of the wells to be fractured in the well group is carried out. The well shut-in time is determined based on the pressure diffusion simulation optimization, or after the well shut-in pressure tends to be stable, the well is opened for production.

[0008] In the step C, an innovative bionic fracturing mode is adopted to achieve differentiated and efficient transformation in different zones. The differentiated bionic fracturing imitates the three-level flight feather mode of bird wings, and the process parameters of the horizontal well are differentiated and bionically designed, which are divided into three zones.

[0009] In step C, in area 1, a short segment and few clusters mode is adopted, with segment length of 45-60m, 3-5 clusters of perforations in each segment, 24-30 holes in a single segment, and annular perforation.

[0010] In step C, in area 2, a medium-length and medium-cluster mode is adopted, with a segment length of 60-80 m, 6 to 8 clusters of perforations in a single segment, and a perforation method of flow limiting + spiral perforation, with 32-40 holes in a single segment.

[0011] In step C, in area three, a long section and multiple clusters mode is adopted, with a section length of 80-100 m, 9-12 clusters of perforations in a single section, and a perforation method of flow limiting + spiral perforation, with 45-60 holes in a single section.

[0012] In step C, in the differentiated bionic fracturing mode, as the depth of the fracturing section decreases, the amount of liquid and proppant dosage in each fracturing section increases step by step, and the amount of liquid and proppant dosage in a single section increases by 3% to 6% for every 60 to 80 m decrease in depth.

[0013] In step C, the differentiated bionic fracturing mode takes into account the optimization of the single well fracturing scale by preventing crosstalk between wells. Based on the geomechanical model of the well group, the wellbore, perforation and process parameters are imported to calculate the fracturing cracks, and the critical construction parameters for preventing crosstalk between well sections are optimized as the upper limit of the actual construction scale.

[0014] When the differentiated bionic fracturing mode is used for fracturing, the mid-long segment multi-cluster mode in area two and area three requires a composite temporary plugging process to increase the complexity of the fracture network, increase the affected area, and promote the spread of artificial fractures throughout the oil reservoir, thereby controlling the reservoir to the greatest extent.

[0015] The advantages of the present invention are: Compared with the prior art, the present invention aims at the serious interference of new well fracturing of horizontal well groups in shale oil reservoirs on existing production wells. After the production wells are pre-injected with CO2 to increase pressure and replenish energy, the new well fracturing construction of the well group is carried out, and the fracturing is carried out in the order from outside to inside. The single well adopts a differentiated fracturing mode, and different process parameters are used in different areas, which improves the energy utilization rate and transformation efficiency, and completes the coordinated fracturing of well group energy replenishment and seam expansion, especially in the deficit area of ​​the horizontal well group production wells. CO2 is injected to replenish energy and increase pressure, which reduces the negative effects of interference between wells. At the same time, CO2 has the effects of viscosity reduction, extraction, and permeability increase, and the production well has a strong oil increase effect, and the recovery rate of the well group is improved. At the same time, an innovative bionic zoning fracturing mode for the horizontal section along the horizontal well has been developed. Based on energy equivalent work, the differentiated regional transformation of the horizontal well group is more justified and operational, the energy utilization rate is improved, and the development efficiency is accelerated and cost-effective. The full-area transformation of the horizontal well group under the well network conditions can be fully and effectively achieved, with cracks spread throughout the oil reservoir of the well group, and the control degree reaches more than 95%. This solves the problem of negative interference between production wells and fracturing wells under the well network conditions, maximizes the transformation effect of the horizontal well group and the degree of reservoir utilization, improves the recovery rate of the well group, and fully releases the potential for increased oil production. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the horizontal well group in the present invention.

[0017] Figure 2 This is a schematic diagram of the bionic differentiated zoning of shale oil horizontal wells in the present invention.

[0018] Figure 2 Middle: 1-horizontal well vertical section, 2-horizontal wellbore, 3-regional boundary, 4-region 1 (short section length + few clusters), 5-region 2 (medium section length + medium number of clusters), 6-region 3 (long section length + many clusters) DETAILED DESCRIPTION

[0019] The shale oil horizontal well group energy supplementation and fracture expansion collaborative fracturing method of the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] As shown in the figure, the shale oil horizontal well group energy supplement and seam expansion coordinated fracturing method of the present invention mainly injects CO2 energy supplement into the production wells of the shale oil horizontal well group in advance during the development of the shale oil reservoir horizontal well group to increase the formation pressure; then fracturing the new wells, fracturing in order from outside to inside, the two wells are alternately fracturing in a zipper-like manner, and a single well adopts a differentiated zoning fracturing mode; until the fracturing construction of all wells in the well group is completed, specifically including the following steps: A: Modeling and simulation to optimize the CO2 injection parameters of production wells in shale oil horizontal well groups, and implement CO2 injection to boost pressure and replenish energy in production wells in advance; Protective CO2 injection to increase the pressure of production wells in advance increases the stress and pore pressure of the produced area, and establishes a high-pressure area to prevent the hydraulic fractures of new wells from suddenly connecting, so as to reduce the negative effects of well interference and fully transform the reservoir; compared with water injection, it has multiple effects. The pore volume that CO2 can enter is smaller than that of water, and it can diffuse and extract in the dense shale oil matrix; indoor nuclear magnetic resonance experiments show that water can enter pore throats larger than 0.1μm, and CO2 can enter pore throats larger than 0.01μm, which improves the replacement efficiency; CO2 injection has the mechanism of "expansion energy enhancement, dissolution viscosity reduction, hydrocarbon extraction, dissolution permeability enhancement, and diffusion replacement". After CO2 injection, the volume of crude oil can expand by 2 times, effectively replenishing the formation energy. After the injection and dissolution of CO2, the viscosity of crude oil can be reduced by 76%, greatly improving the flow capacity of crude oil. After CO2 injection, the content of carbonate minerals in the reservoir is greatly reduced, calcite and dolomite are almost completely dissolved, and the permeability increases by 1-3 orders of magnitude. In this step, a three-dimensional finite element geomechanical model and a three-dimensional shale gas seepage model are established based on the results of three-dimensional geological modeling, taking into account Hooke's law and the effective stress law. The three-dimensional pore pressure change is used as the boundary condition to calculate the change of ground stress at different times after the production well is pressurized, and finally the pore pressure and ground stress range of the production well during long-term exploitation are determined; Specifically, a small-layer structural stratigraphic matrix model is established in the horizontal well group area, and the seismic inversion porosity and saturation volumes are used as trend constraints, and the sequential Gaussian method is applied to establish a matrix attribute model; Specifically, a fracture model is established. Based on seismic data and the properties of ant bodies, the overall distribution of fractures in the well group area is clarified. Combined with the fracture development intensity of well logging, large-scale, medium-scale and small-scale DFN fracture models are established. Specifically, a geostress model is established, and a geostress field model is constructed by using finite element simulation based on a three-dimensional geological model, using the well group brittleness index, rock mechanics characteristic parameters, and fracture distribution and geostress orientation parameters obtained by imaging logging; Specifically, a reservoir-fluid-rock model is established. Based on the monitoring data of production well fracturing transformation, transformation SRV, and fracture morphology, and taking into account reservoir damage and rupture, matrix filtration, and interactive deformation between rocks and fractures, a production well fracturing network expansion model is established. The dynamic evolution of geostress after production well fracturing is evaluated to determine the pore pressure and geostress spread range of the production well. The zoned phase permeability is used to characterize the differences in physical properties of different reservoirs and flow media, and an equivalent permeability field of fracture distribution is established.

[0021] Specifically, the CO2 injection scale is optimized, different gas injection volumes are simulated, the oil increase effect and oil change rate are compared, and the injection volume with a significant increase in oil increase is preferred. The bottom hole pressure rises faster after gas injection diffusion, and the bottom hole pressure is increased to achieve the purpose of reducing interference; and the pressure diffusion is simulated to optimize the well shut-in time, or the well is opened for production when the well shut-in pressure tends to be stable. If the well shut-in time is too short, it will not fully react with the formation fluid, resulting in waste; if the well shut-in time is too long, the gas diffusion will be serious, CO2 will not be able to carry crude oil out, and the utilization rate will decrease.

[0022] B: Conduct fracturing construction of new wells in shale oil horizontal well groups, fracturing from outside to inside; In this step, the outermost horizontal well in the fracturing shale oil horizontal well group is preferentially selected, and then fracturing is performed one by one from the outside to the inside; the wellhead fracturing processes of the horizontal wells on both sides are connected, and the process conversion is realized through the diversion manifold, and a set of fracturing vehicles is shared to perform zipper fracturing of the two wells alternately without interruption; Specifically, sequential fracturing from the outside to the inside gathers energy inside the well group to form a high-pressure area, increase the formation pressure coefficient, reduce the horizontal two-way stress difference, change the original stress field, and increase the complexity of the transformation; C: Carry out differentiated fracturing in the horizontal fracturing section of a single well, divide the horizontal section into three areas, and design the perforation, segmentation, and scale parameters of each area differently; use a low-viscosity fracturing fluid system, large displacement, and large fluid volume to create a complex fracture network; Specifically, based on the principle of energy equivalence, under large-volume construction conditions, the fracturing fluid flows at high speed in a pipe with an inner diameter of 115 mm, and a large shear force is generated inside the fluid, which is proportional to the flow velocity gradient. The greater the flow velocity, the greater the shear force. Large-volume construction leads to greater friction resistance between the fluid and the inner wall of the pipe. Moreover, the longer the wellbore, the greater the friction resistance along the way, the greater the energy loss, and the weakened energy of rock breaking and fracture creation. The innovative bionic fracturing mode is adopted, and the zone-differentiated efficient transformation is carried out to improve the efficiency of fracture creation.

[0023] Specifically, differentiated bionic fracturing imitates the three-level flight feather pattern of bird wings (outer primary flight feathers - thicker feather shaft, large and sparse feathers; secondary flight feathers - medium feather shaft, medium feathers; tertiary flight feathers - thinner feather shaft, small and dense feathers), and differentiates the bionic design of horizontal well process parameters, which are divided into three areas; Furthermore, the differentiated bionic fracturing, in area 1, adopts a short segment length and small cluster number mode, with a segment length of 45-60m, 3-5 clusters of perforations in each segment, 24-30 holes in a single segment, and annular perforation and large-aperture bullet perforation to reduce hole friction, facilitate energy accumulation, and enhance the internal fracture creation capacity of the fracture; Furthermore, the differentiated bionic fracturing, in area 2, adopts a medium-length and medium-cluster mode, with a segment length of 60-80m, 6 to 8 clusters of perforations in a single segment, and a perforation method of flow limiting + spiral perforation, with 32-40 holes in a single segment.

[0024] Furthermore, the differentiated bionic fracturing, in area three, adopts a long-segment and multi-cluster mode, with a segment length of 80-100m, 9 to 12 clusters of perforations in a single segment, and a perforation method of flow limiting + spiral perforation, with 45-60 holes in a single segment.

[0025] Furthermore, in the differentiated bionic fracturing mode, as the depth of the fracturing section decreases, the amount of liquid and proppant dosage in each fracturing section increases step by step, and the amount of liquid and proppant dosage in a single section increases by 3% to 6% for every 60 to 80 meter decrease in depth.

[0026] Furthermore, the differentiated bionic fracturing mode takes into account the optimization of the single-well fracturing scale by preventing crosstalk between wells. Based on the geomechanical model of the well group, the wellbore, perforation and process parameters are imported to calculate the fracturing cracks, and the critical construction parameters for preventing crosstalk between well sections are optimized as the upper limit of the actual construction scale.

[0027] Furthermore, when the differentiated bionic fracturing mode is used for fracturing, the mid-long section multi-cluster mode in Area 2 and Area 3 performs 1-2 times of composite temporary plugging to promote the lateral expansion of the fracture layer throughout the reservoir, increase the density and complexity of the fracture network, realize bionic fracture network transformation, and maximize the coverage of the fracture on the inter-well plane transformation area.

[0028] D: After completing the fracturing of each horizontal well in the shale oil horizontal well group, the well is shut down and when the wellhead pressure diffuses to a stable state, the well is opened for production.

[0029] Through this process, CO2 is injected into production wells to supplement energy and increase pressure, and fracturing wells are efficiently transformed by bionic differentiated zoning, so that the entire area of ​​the horizontal well group under well network conditions can be fully and efficiently transformed, the production wells have a good oil increase effect, the fracturing wells reduce costs and increase efficiency, and the development efficiency and economic benefits of the well group are improved.

[0030] The following is the process and effect of using the design method of the present invention in actual field: A shale oil reservoir in the Subei Basin was developed using a shale oil horizontal well group, with the risk exploration well SQ1HF being deployed first. After the initial fracturing transformation, a 4mm nozzle was used for spraying production, with a daily production peak of 66.3t, achieving an exploration breakthrough. Subsequently, two horizontal wells were deployed on both sides of the SQ1HF well in the same layer, with a horizontal section length of 1534 to 1804 meters.

[0031] First, the production well SQ1HF was studied by CO2 injection. Based on the modeling numerical model, CO2 injection simulation was carried out to optimize the CO2 injection volume and pressure diffusion time. The designed gas injection volume was 17,000 tons, the gas injection rate was 550-650 tons / day, and the gas injection pressure was 31-38MPa. After the injection, the well was turned into the soaking stage. After the high-pressure zone was established in the fracture area of ​​the SQ1HF well, the new well construction of the well group to be fractured was carried out.

[0032] Conduct fracturing construction of new wells in shale oil horizontal well groups, fracturing from outside to inside; Priority is given to connecting the wellhead fracturing processes of the two horizontal wells (well 1 to be killed and well 4 to be killed) outside the well group, realizing process conversion through the diversion manifold, and sharing a set of fracturing vehicles to carry out uninterrupted alternating zipper fracturing of the two wells.

[0033] A single horizontal well adopts a bionic zoned fracturing mode, which is divided into three areas: Process parameters of area 1: segment length 45-60m, 4 clusters of perforations in a single stage, 28 holes in total, large-aperture perforating bullet BH42RDX28-2, aperture 16mm, perforation method is annular perforation, single-stage fracturing fluid volume 3910-4160 cubic meters, single-stage proppant dosage 108-127 cubic meters, injection displacement 16-18 cubic meters / minute.

[0034] Process parameters for area 2: segment length 60-80m, single-stage flow-limiting perforation 8 clusters, total number of holes 40, ultra-deep penetrating bullet SDP36RDX24-2, aperture 9.2mm, 60° phase angle, spiral hole arrangement, single-stage fracturing fluid volume 4250-4690 cubic meters, single-stage proppant dosage 135-156 cubic meters, injection displacement 18-20 cubic meters / minute. One composite temporary plugging was adopted, with 200kg of temporary plugging agent and 20 temporary plugging balls, to promote uniform expansion of cracks in multiple perforation clusters.

[0035] Process parameters for area three: segment length 80-100m, single-stage perforation 10 clusters, total number of holes 60 holes, ultra-deep penetrating bullet SDP36RDX24-2, aperture 9.2mm, 60° phase angle, spiral hole arrangement, single-stage fracturing fluid volume 4870-6060 cubic meters, single-stage proppant dosage 160-186 cubic meters, injection displacement 18-20 cubic meters / minute. Two composite temporary pluggings were adopted, with a single injection of 200kg of temporary plugging agent and 30 temporary plugging balls, to promote uniform transformation of cracks in multiple perforation clusters.

[0036] After the two horizontal wells on the outside of the well group (Well 1 to be killed and Well 4 to be killed) are fractured, they are then shut down, and then the two horizontal wells on the inside (Well 2 to be killed and Well 3 to be killed) are fractured until all the wells in the well group are fractured.

[0037] The implementation effect after the actual implementation of the method of the present invention: After the SQ1HF well was shut down for 53 days, the daily pressure drop of the wellhead pressure was less than 0.1MPa, and the well was opened for production. The wellhead pressure was 25.7MPa, the daily oil production was 30 tons, and the average formation pressure was increased by 19MPa compared with before gas injection, and the stage recovery rate was increased by 3.6%. When the daily pressure drop of the wellhead pressure of the fracturing well was less than 0.1MPa, the well was opened for production, and the average daily oil production of a single well reached 48.9 tons / day, and the production increase potential of the well group oil reservoir was fully utilized. Compared with the conventional transformation mode, the hydraulic fractures formed by the well group energy expansion and coordinated fracturing can achieve the maximum degree of fracture control of the reservoir, the time efficiency is increased by 9%, the construction cost is reduced by 3%, and the development efficiency and economic benefits of the well group are improved.

Claims

1. A shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method, characterized in that: The following steps are involved: A: Modeling and simulation to optimize the CO2 injection parameters of production wells in shale oil horizontal well groups, and inject CO2 to boost pressure and replenish energy in production wells in advance; In this step, a three-dimensional finite element geomechanical model of a shale oil horizontal well group and a three-dimensional shale gas seepage model are established. Taking the three-dimensional pore pressure change as the boundary condition, the changes in the ground stress at different times after the production well pressure is calculated, and finally the pore pressure and ground stress range of the production well for long-term exploitation are determined; then the CO2 injection is simulated to increase the pressure and replenish the energy in the production area, the CO2 injection amount is optimally determined, and the CO2 injection is implemented in the production well to increase the formation pressure in the production well fracture network and the well group area; B: Conduct fracturing construction of new wells in shale oil horizontal well groups, fracturing from outside to inside; In this step, the outermost horizontal well in the fracturing shale oil horizontal well group is preferentially selected, and then fracturing is performed one by one from the outside to the inside; the wellhead fracturing processes of the horizontal wells on both sides are connected, and the process conversion is realized through the diversion manifold, and a set of fracturing vehicles is shared to perform uninterrupted alternating zipper fracturing of the two wells; C: Carry out differentiated fracturing in the horizontal fracturing section of a single well, divide the horizontal section into three areas, and design the perforation, segmentation, and scale parameters of each area differently; use a low-viscosity fracturing fluid system, large displacement, and large fluid volume to create a complex fracture network; D: After completing the fracturing of each horizontal well in the shale oil horizontal well group, the well is shut down and when the wellhead pressure diffuses to a stable state, the well is opened for production.

2. The shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method according to claim 1, characterized in that: In the step A, a well group sub-layer structural stratum matrix model is established, and a matrix attribute model is established by using a seismic inversion porosity body and a saturation body as trend constraints and applying a sequential Gaussian method; Establish a fracture model. Based on seismic data and ant body attributes, clarify the overall distribution of fractures in the well group area. Combined with the well logging fracture development intensity, establish large-scale, medium-scale and small-scale DFN fracture models. Establish a geostress model, using the well group brittleness index, rock mechanics characteristic parameters, and the fracture distribution and geostress orientation parameters obtained by imaging logging, and use finite element simulation on the basis of the three-dimensional geological model to construct a geostress field model; Establish a reservoir-fluid-rock model, based on the monitoring data of production well fracturing, transformation SRV, and fracture morphology, consider the damage and fracture of the reservoir, matrix filtration, and the interactive deformation of rock and fractures, establish a production well fracturing network expansion model, evaluate the dynamic evolution of geostress after production well fracturing, and determine the pore pressure and geostress range of the production well; The regional phase permeability is used to characterize the differences in reservoir physical properties and flow media, and the equivalent permeability field of fracture distribution is established.

3. The shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method according to claim 1, characterized in that: In step A, the CO2 injection scale is optimized, different gas injection volumes are simulated, and the injection volume with a significant increase in oil production is preferred. The pressure diffusion optimization is simulated to determine the well shut-in time or wait for the well shut-in pressure to stabilize before opening the well for production.

4. The shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method according to claim 1, characterized in that: In the step C, an innovative bionic fracturing mode is adopted to achieve differentiated and efficient transformation in different zones. The differentiated bionic fracturing imitates the three-level flight feather mode of bird wings, and the process parameters of the horizontal well are differentiated and bionically designed, which are divided into three zones.

5. The shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method according to claim 4, characterized in that: In step C, in area 1, a short segment and few clusters mode is adopted, with segment length of 45-60m, 3-5 clusters of perforations in each segment, 24-30 holes in a single segment, and annular perforation.

6. The method for energy supplementation and seam expansion coordinated fracturing of a shale oil horizontal well group according to claim 4 or 5, characterized in that: In step C, in area 2, a medium-length and medium-cluster mode is adopted, with a segment length of 60-80 m, 6 to 8 clusters of perforations in a single segment, and a perforation method of flow limiting + spiral perforation, with 32-40 holes in a single segment.

7. The shale oil horizontal well group energy supplementation and seam expansion collaborative fracturing method according to claim 6, characterized in that: In step C, in area three, a long section and multiple clusters mode is adopted, with a section length of 80-100 m, 9-12 clusters of perforations in a single section, and a perforation method of flow limiting + spiral perforation, with 45-60 holes in a single section.

8. The method for energy supplementation and seam expansion coordinated fracturing of a shale oil horizontal well group according to claim 4, 5 or 7, characterized in that: In step C, in the differentiated bionic fracturing mode, as the depth of the fracturing section decreases, the amount of liquid and proppant dosage in each fracturing section increases step by step, and the amount of liquid and proppant dosage in a single section increases by 3% to 6% for every 60 to 80 m decrease in depth.

9. The method for energy supplementation and seam expansion coordinated fracturing of a shale oil horizontal well group according to claim 8, characterized in that: In step C, the differentiated bionic fracturing mode takes into account the optimization of the single well fracturing scale by preventing crosstalk between wells. Based on the geomechanical model of the well group, the wellbore, perforation and process parameters are imported to calculate the fracturing cracks, and the critical construction parameters for preventing crosstalk between well sections are optimized as the upper limit of the actual construction scale.

10. The shale oil horizontal well group energy supplementation and seam expansion coordinated fracturing method according to claim 9, characterized in that: When the differentiated bionic fracturing mode is used for fracturing, the mid-long segment multi-cluster mode in area two and area three requires a composite temporary plugging process to increase the complexity of the fracture network, increase the affected area, and promote the spread of artificial fractures throughout the oil reservoir, thereby controlling the reservoir to the greatest extent.

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