Geological design method and device for thick-layer compact sandstone horizontal well segmented fracturing horizontal section

Abstract

The application discloses a method and device for geologic design of a thick-layered compact sandstone horizontal well segmented fracturing horizontal section. According to the scheme, the method comprises the following steps: fine analysis of thick-layered compact sandstone geologic engineering parameters and establishment of a fracturing model, calculation of in-layer segmented rock mechanics parameters and simulation of high longitudinal extension of a fracturing crack, optimization design of a horizontal well drilling layer section, optimization of distribution of a horizontal wellbore section annular horizontal wellbore section perforation position, and optimization design of fracturing crack parameters and well pattern and well spacing, so that the high direction of the fracturing crack is balanced in extension, and the maximum degree of use of longitudinal reserves is achieved.

Description

Technical Field

[0001] This application pertains to the field of field fracturing in oil and gas fields, and more specifically, relates to the geological design method and apparatus for the horizontal section of a segmented fracturing operation in a horizontal well in thick, tight sandstone. Background Technology

[0002] Horizontal well fracturing is a crucial technique for developing tight sandstone oil and gas reservoirs, and the geological design of the horizontal section is a vital geological foundation determining the fracturing effect and post-fracturing production capacity. Currently, the main factors considered in horizontal well fracturing geological design schemes include: optimizing the horizontal section length based on the planar distribution and scale of the tight reservoir and the single-well production target; optimizing fracture spacing, perforation method, and fracturing parameters based on the planar heterogeneity of the facies-controlled reservoir.

[0003] In one design scheme, the orientation of the horizontal section is determined by the distribution direction of the geostress field. This design scheme is effective in tight sandstone reservoirs dominated by thin or interbedded lacustrine sedimentary layers (sandstone thickness generally less than 20m). The horizontal section of the horizontal well is typically located in the middle of the sand body, allowing the longitudinal propagation of fracturing fractures to penetrate the entire sand layer. This has achieved good fracturing stimulation results and enabled effective utilization of reserves. It has yielded good development results in tight sandstone oil and gas fields in the Ordos Basin and Sichuan Basin.

[0004] For large-scale, extremely thick (generally greater than 50m) tight sandstone reservoirs in foreland basins like those in North America, hydraulic fracturing is necessary to stimulate oil and gas production. Sandstone deposition is controlled by marine transgression and regression, resulting in multi-cycle, rhythmic reservoir distribution. The reservoir's internal physical and rock mechanical properties exhibit significant heterogeneity, strongly controlling the vertical propagation of hydraulic fracturing fractures. This vertical propagation is asymmetrically distributed due to the influence of reservoir depositional cycles and physical properties. Therefore, for hydraulic fracturing design in thick, tight sandstone reservoirs, optimizing the design location of the horizontal fracturing section along the reservoir's vertical direction to achieve balanced propagation and maximize vertical reservoir utilization is crucial.

[0005] Focusing on the geological design method of horizontal fracturing in thick, tight sandstone horizontal wells, the Derwent database, the State Intellectual Property Office patent database, and the Tsinghua Tongfang CNKI journal database were searched to obtain the following publicly available patents and documents.

[0006] Patent application "A method for optimizing perforation parameters to improve the fracturing efficiency of multi-cluster perforations in horizontal well sections (CN202010674549A)" establishes a quasi-three-dimensional model and a flow-limited fracturing model for each cluster of perforations. It derives the relationships that the perforation diameters of each perforation cluster should satisfy during flow-limited fracturing, thereby accurately determining the number of perforations and the cluster length of each cluster, achieving uniform fracturing initiation within the horizontal well section. However, this scheme does not address the impact of reservoir longitudinal heterogeneity on the highly uniform propagation of fractures, and is therefore unsuitable for optimizing perforation parameters in thick, tight sandstone reservoirs.

[0007] The patent application "An optimization method, medium, terminal and device for the distribution of fractured horizontal well network (CN202010008793.7)" establishes a non-intersecting constraint optimization model for the fractured horizontal well network, and simultaneously optimizes parameters such as well network form, number of wells, horizontal well inclination and length, perforation location and fracture properties. However, it does not fully consider the influence of reservoir vertical heterogeneity on high fracture propagation, and does not optimize the design of the drilling interval of horizontal wells and the perforation hole distribution of the annular horizontal well section based on high fracture propagation. Therefore, it is not suitable for the geological design of fractured thick tight sandstone reservoirs.

[0008] The patent application "Horizontal Well Hydraulic Fracturing Perforation Method (CN201510794657.4)" designs all perforations within a single perforation cluster in a horizontal well to be located in the same plane parallel to the orientation of the maximum principal geostress in the formation where the horizontal well is located, thereby reducing fracturing construction pressure and improving the communication between the wellbore and the reservoir. However, it does not consider the impact of the heterogeneity of the longitudinal geostress in the reservoir on the propagation of the fracture height, nor does it propose a reasonable perforation position adjustment scheme for the uneven propagation of the fracture height.

[0009] The patent application "A method for optimizing perforation sites for volumetric fracturing using well logging data (CN201510433840.1)" uses well logging data to calculate the dynamic Young's modulus and dynamic Poisson's ratio of different layers, and calculates the mechanical brittleness index and compressibility index of the layers, providing a decision-making basis for optimizing perforation sites for volumetric fracturing. However, it does not propose a reasonable optimization scheme for the distribution of perforation locations to address the uneven propagation of longitudinal fracturing fractures in reservoirs, making it difficult to achieve fine optimization design and full stimulation of fracturing geology in tight and thick sandstone reservoirs.

[0010] The literature "Research on Geological Optimization Design of Different Types of Horizontal Wells in the Ordos Basin" studies the geological optimization design of horizontal wells from aspects such as horizontal well orientation, horizontal well length, horizontal well distance from top, horizontal well distance from edge water, and perforation method. However, it does not propose an optimization scheme for the drilling section and perforation location of fractured horizontal wells with uneven vertical expansion of fractures.

[0011] The literature "Case Study on the Influence of Perforation Parameters on Hydraulic Fracturing Effect" studies the impact of perforation parameters on fracturing operations and compares field application examples to find the influence of perforation depth, perforation orientation, and perforation height on the propagation of fracturing fractures. However, it does not propose an optimization scheme for the perforation location in case of uneven longitudinal propagation of fracturing fractures, and is not applicable to the geological design optimization of fracturing in thick tight sandstone reservoirs.

[0012] In summary, although research on the optimization of geological design for horizontal well fracturing is receiving increasing attention, in-depth research has not been conducted on the highly uneven propagation of fractures caused by the heterogeneity of the vertical geological engineering characteristics of the reservoir. Research on the optimization of the drilling intervals and perforation distribution locations of horizontal wells fracturing in thick and tight sandstone reservoirs is still lacking. Summary of the Invention

[0013] In view of this, this application proposes a geological design method for the horizontal section of a horizontal well in thick, tight sandstone formation, to achieve relatively balanced fracture propagation in the vertical direction and maximize the utilization of reserves in the vertical direction. This application also provides corresponding devices, electronic equipment, and media.

[0014] In a first aspect, embodiments of this application provide a geological design method for the horizontal section of a segmented fracturing operation in a thick, tight sandstone horizontal well, including:

[0015] Step S1: Based on the fracturing geological engineering parameters of the target area, the scale of fracturing construction and the range of longitudinal and transverse reservoir modification, establish a fracturing area geological model of the target block. The target area is a thick, tight sandstone, and the target block is located in the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block.

[0016] Step S2: Based on the heterogeneity of the geological and engineering characteristics of the target block, the target block is initially divided into multiple layers;

[0017] Step S3: Establish a rock mechanics model for each layer segment, wherein the rock mechanics model is used to describe the rock mechanics parameters of the corresponding layer segment;

[0018] Step S4: Based on the geological model of the fracturing area and the rock mechanics model corresponding to each layer, simulate the vertical extension of the fracturing fractures in each layer of the target block;

[0019] Step S5: Based on the longitudinal extension of the hydraulic fracture, determine the location of the horizontal well drilling in each section and the location and number of perforations in the annular horizontal wellbore section;

[0020] Step S6: Based on the determined horizontal well drilling locations and the locations and number of perforations in the annular horizontal well section, determine the fracture parameters and well layout parameters to be used for fracturing.

[0021] As a specific implementation of this application embodiment, step S3, establishing the rock mechanics model corresponding to each layer segment specifically includes:

[0022] For each layer, based on the well logging and geological data of that layer, a rock mechanics parameter calculation model corresponding to that layer is selected, and the rock mechanics parameters of that layer are calculated to obtain the rock mechanics model corresponding to that layer.

[0023] As a specific implementation of this application embodiment, in step S5, determining the horizontal well drilling location of each segment based on the vertical extension of the hydraulic fracture height specifically includes: for each segment...

[0024] If the resistance to the expansion of the fracture height in the upper part of the layer is large, and the fracture height expands downward, the horizontal well drilling position is set to be above the middle of the layer.

[0025] If the lower part of the formation has high resistance to fracture height expansion and the fracture height expands upwards, the horizontal well drilling location should be set below the middle of the formation.

[0026] If the longitudinal fracture height of the formation is uniform, or the difference in resistance between the upper and lower parts of the longitudinal fracture height is small, the horizontal well drilling location is set in the middle of the formation.

[0027] As a specific implementation of this application embodiment, in step S5, the location and number of perforations in the annular horizontal wellbore section of each segment are determined based on the longitudinal extension of the hydraulic fracture height. Specifically, this includes: for each segment,

[0028] If the fracture height of this section extends downwards, increase the number of perforations above the annular horizontal wellbore section and decrease the number of perforations below the annular horizontal wellbore interface.

[0029] If the fracture height of the segment extends upwards, increase the number of perforations below the annular horizontal wellbore section and decrease the number of perforations above the annular horizontal wellbore interface;

[0030] If the fracture height of the segment expands uniformly in the longitudinal direction, then perforations are evenly arranged on the annular horizontal wellbore cross-section.

[0031] As a specific implementation of this application embodiment, the feature is that, in step S5, based on the longitudinal extension of the hydraulic fracture height, the drilling location of the horizontal well in each section and the location and number of perforations in the annular horizontal wellbore section are determined, specifically including:

[0032] First, determine the location of the horizontal well drilling in each section based on the longitudinal extension of the fracture height;

[0033] Then, based on the determined horizontal well drilling locations for each segment, and according to the longitudinal extension of the fracture height, the location and number of perforations in the annular horizontal wellbore section for each segment are determined.

[0034] As a specific implementation of this application, the fracture parameters include the fracture length and the spacing between segments, and the well layout parameters include the well network spacing.

[0035] As a specific implementation of this application embodiment, step S6 specifically includes:

[0036] The horizontal well drilling location and the perforation location and number at the annular horizontal wellbore interface in the fracturing well production capacity prediction model are set to the determined horizontal well drilling location and the perforation location and number at the annular horizontal wellbore interface. The fracturing well production capacity prediction model is used to predict the corresponding production capacity based on fracturing parameters and well layout parameters.

[0037] The fracture parameters and well placement parameters to be used in fracturing are determined based on the production capacity forecast results.

[0038] Secondly, embodiments of this application also provide an electronic device, which includes:

[0039] Memory, which stores executable instructions;

[0040] A processor that executes the executable instructions in the memory to implement the geological design method for the horizontal section of a thick, tight sandstone horizontal well with segmented fracturing.

[0041] Thirdly, embodiments of this application also provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the geological design method for the segmented fracturing horizontal section of a thick, tight sandstone horizontal well.

[0042] Fourthly, this application also provides a geological design device for the horizontal section of a thick, tight sandstone horizontal well undergoing segmented fracturing, comprising:

[0043] The fracturing area geological model establishment unit is used to establish a fracturing area geological model of the target block based on the fracturing geological engineering parameters, fracturing construction scale and reservoir longitudinal and transverse modification range of the target area. The target area is a thick tight sandstone, and the target block is located in the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block.

[0044] The intra-layer segment division unit is used to initially divide the target block into multiple segments based on the heterogeneity of the geological and engineering characteristics of the target block;

[0045] The rock mechanics model building unit is used to build a rock mechanics model corresponding to each layer, and the rock mechanics model is used to describe the rock mechanics parameters of the corresponding layer.

[0046] The high vertical propagation simulation unit for hydraulic fractures is used to simulate the high vertical propagation of hydraulic fractures in each segment of the target block based on the geological model of the hydraulic fracture area and the rock mechanics model corresponding to each segment.

[0047] The drilling location and annular horizontal wellbore section perforation design unit is used to determine the drilling location and annular horizontal wellbore section perforation location and number for each segment based on the longitudinal extension of the hydraulic fracture.

[0048] The fracturing parameter and well layout parameter determination unit is used to determine the fracture parameters and well layout parameters to be used for fracturing based on the determined drilling location of the horizontal well and the location and number of perforations in the annular horizontal well section.

[0049] Through the above embodiments, a geological design scheme for the horizontal section of a horizontal well in thick tight sandstone is proposed, including detailed analysis of geological engineering parameters of thick tight sandstone and establishment of a fracturing model, calculation of segmented rock mechanics parameters within the layer and simulation of vertical fracture propagation, optimized design of the drilling sections encountered by the horizontal well, optimization of the perforation location distribution of the annular horizontal wellbore, and optimized design of fracturing parameters and well network spacing. According to this application, based on regional fracturing geological models and rock mechanics parameter models, the propagation law of high-fracture depth is simulated and studied. The drilling sections encountered by the horizontal well and the perforation locations of the annular horizontal wellbore are optimized to address the uneven vertical fracture depth propagation, promoting uniform propagation of high-fracture depth in thick, heterogeneous reservoirs. Based on the predicted production capacity of the fracturing well, the parameters of the fracturing fracture and well network spacing are optimized, completing the optimized design of the fracturing geological scheme for thick, tight sandstone reservoirs. The optimized fracturing geological scheme provided in this application can maximize the degree and effect of fracturing stimulation, achieve full stimulation of thick tight sandstone reservoirs, and improve oil and gas field recovery and economic benefits.

[0050] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0051] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.

[0052] Figure 1 A flowchart is shown of a geological design method for the horizontal section of a thick, tight sandstone horizontal well fracturing according to an embodiment of this application.

[0053] Figures 2(a), (b) and (c) illustrate schematic diagrams of horizontal well drilling location optimization design according to exemplary embodiments of this application.

[0054] Figures 3(a), (b) and (c) show schematic diagrams of perforation optimization design for annular horizontal wellbore sections according to exemplary embodiments of this application.

[0055] Figure 4 A schematic diagram of a fracturing zone geological model according to an exemplary embodiment of this application is shown.

[0056] Figure 5 A schematic diagram of the minimum horizontal principal stress curve of the target block obtained according to an exemplary embodiment of this application is shown.

[0057] Figure 6 A schematic diagram of simulated high propagation of a hydraulic fracture is shown after setting the drilling location of a horizontal well according to an exemplary embodiment of this application. Detailed Implementation

[0058] Preferred embodiments of this application will now be described in more detail. While preferred embodiments of this application are described below, it should be understood that this application can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0059] Example 1

[0060] Figure 1 A flowchart illustrating a geological design method for the horizontal section of a staged fracturing operation in a thick, tight sandstone horizontal well according to an embodiment of this application is shown. Figure 1 As shown, the method includes steps S1 to S6.

[0061] Step S1: Based on the fracturing geological engineering parameters of the target area, the scale of fracturing operations, and the range of longitudinal and transverse reservoir modification, establish a fracturing area geological model of the target block. The target area is a thick, tight sandstone layer, and the target block is located within the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block.

[0062] It can comprehensively collect fracturing geological engineering parameters of thick, tight sandstone in the target area, such as the mineral composition, total organic carbon content, porosity, rock elastic modulus, Poisson's ratio, fracture toughness, and development of natural fractures in the drilled layers, and conduct detailed analysis of the main controlling geological engineering factors affecting the fracturing effect, clarify the heterogeneous distribution characteristics of vertical geological engineering parameters, and establish a regional fracturing geological model based on a full assessment of the scale of fracturing operations and the range of longitudinal and lateral reservoir modification.

[0063] Step S2: Based on the heterogeneity of the geological and engineering characteristics of the target block, the target block is initially divided into multiple layers.

[0064] Based on the vertical geological and engineering characteristics of the heterogeneity of thick dense sandstone, the layers can be preliminarily divided into segments. For example, based on the vertical heterogeneity of porosity, permeability, water saturation, Young's modulus, Poisson's ratio, etc., the thick dense sandstone can be divided into multiple segments.

[0065] Step S3: Establish a rock mechanics model for each layer segment, which is used to describe the rock mechanics parameters of the corresponding layer segment.

[0066] In some possible implementations, establishing a rock mechanics model corresponding to each layer specifically includes:

[0067] For each layer, based on the well logging and geological data of that layer, a rock mechanics parameter calculation model corresponding to that layer is selected, and the rock mechanics parameters of that layer are calculated to obtain the rock mechanics model corresponding to that layer.

[0068] Based on well logging and geological data from different formations, appropriate rock mechanics parameter calculation models can be selected to accurately calculate rock mechanics parameters such as Young's modulus, Poisson's ratio, maximum horizontal principal stress, minimum horizontal principal stress, and fracture pressure for different formations, thus establishing a rock mechanics model for that formation. Rock mechanics models can include Young's modulus models, Poisson's ratio models, maximum horizontal principal stress models, minimum horizontal principal stress models, fracture pressure models, and so on.

[0069] According to this application, rock mechanics models for each layer can be accurately obtained, which is beneficial to significantly improving the accuracy of the geological design of the final horizontal well segmented fracturing horizontal section.

[0070] Step S4: Based on the geological model of the fractured area and the rock mechanics model corresponding to each layer, simulate the vertical extension of the fractures in each layer of the target block.

[0071] This method allows for the study of the influence of reservoir vertical rock mechanical parameter heterogeneity on high-amplitude fracture propagation. It enables the simulation of high vertical fracture propagation based on a refined model of the geological and rock mechanical parameters of the fractured area. For example, for each segment, a pumping program can be invoked to simulate high vertical fracture propagation based on the geological and rock mechanical parameters of that segment.

[0072] Step S5: Based on the longitudinal extension of the fracture height, determine the horizontal well drilling location and the location and number of perforations in the annular horizontal wellbore section for each segment.

[0073] In one possible implementation, determining the horizontal well encounter location for each segment based on the vertical extension of the hydraulic fracture height specifically includes: for each segment...

[0074] If the resistance to the expansion of the fracture height in the upper part of the layer is large, and the fracture height expands downward, the horizontal well drilling position is set to be above the middle of the layer.

[0075] If the lower part of the formation has high resistance to fracture height expansion and the fracture height expands upwards, the horizontal well drilling location should be set below the middle of the formation.

[0076] If the longitudinal fracture height of the formation is uniform, or the difference in resistance between the upper and lower parts of the longitudinal fracture height is small, the horizontal well drilling location is set in the middle of the formation.

[0077] Figures 2(a), (b), and (c) illustrate schematic diagrams of the optimized design of horizontal well drilling locations according to exemplary embodiments of this application. As shown in Figure 2(a), the upper part of the reservoir has high resistance to fracture height expansion, and the fracture height expands downwards, so the horizontal well drilling location is set above the middle of the reservoir; as shown in Figure 2(b), the longitudinal fracture height expansion of the reservoir is relatively uniform or the difference in resistance between the upper and lower fracture height expansion is small, so the horizontal well drilling section is set in the middle of the reservoir; as shown in Figure 2(c), the lower part of the reservoir has high resistance to fracture height expansion, and the fracture height expands upwards, so the horizontal well drilling section is located below the middle of the reservoir.

[0078] The horizontal well drilling location can be repeatedly adjusted to observe the simulated high propagation of the fracture. Then, the horizontal well drilling location corresponding to the more ideal high propagation of the fracture is determined as the horizontal well drilling location used for fracturing.

[0079] According to this application, based on understanding the law of uneven longitudinal fracture height expansion, the drilling location of horizontal wells is optimized, breaking the inherent design concept that the drilled horizontal well section is located in the middle of the reservoir in the vertical direction. The drilling location of the horizontal well section is adjusted upward or downward according to the characteristics of uneven longitudinal fracture height expansion, so that the fracture height can achieve balanced expansion in the vertically heterogeneous reservoir to the greatest extent.

[0080] In one possible implementation, the location and number of perforations in the annular horizontal wellbore section of each segment are determined based on the longitudinal extension of the hydraulic fracture, specifically including: for each segment,

[0081] If the fracture height of this section extends downwards, increase the number of perforations above the annular horizontal wellbore section and decrease the number of perforations below the annular horizontal wellbore interface.

[0082] If the fracture height of the segment extends upwards, increase the number of perforations below the annular horizontal wellbore section and decrease the number of perforations above the annular horizontal wellbore interface;

[0083] If the fracture height of the segment expands uniformly in the longitudinal direction, then perforations are evenly arranged on the annular horizontal wellbore cross-section.

[0084] Figures 3(a), (b), and (c) illustrate schematic diagrams of perforation optimization design for annular horizontal wellbore sections according to exemplary embodiments of this application. As shown in Figure 3(a), based on the optimized drilling section of the horizontal well, the fracture height is extended downwards, and perforation can be performed only above the annular horizontal wellbore section, or the number of perforations above the annular horizontal wellbore section can be increased while the number of perforations below the annular horizontal wellbore section can be reduced. For example, in this example, perforation is performed only above the annular horizontal wellbore section. As shown in Figure 3(b), based on the optimized drilling section of the horizontal well, the fracture height is extended uniformly in the longitudinal direction, and perforation is performed uniformly in the annular horizontal wellbore section. As shown in Figure 3(c), based on the optimized drilling section of the horizontal well, the fracture height is extended upwards, and perforation can be performed only below the annular horizontal wellbore section, or the number of perforations below the annular horizontal wellbore section can be increased while the number of perforations above the annular horizontal wellbore section can be reduced. For example, in this example, perforation is performed only below the annular horizontal wellbore section.

[0085] The position and number of perforations in the annular horizontal wellbore section can be repeatedly adjusted to observe the simulated high propagation of the hydraulic fracture. Then, the position and number of perforations in the annular horizontal wellbore section corresponding to the ideal high propagation of the hydraulic fracture can be determined as the position and number of perforations in the annular horizontal wellbore section used for hydraulic fracturing.

[0086] The perforation of the annular horizontal wellbore section according to this application differs from conventional uniform full-coverage perforation. Instead, it optimizes the number of perforations and related parameters in the upper and lower parts of the annular horizontal wellbore section based on the longitudinal expansion of the fracture height, thereby promoting the uniform longitudinal expansion of the fracture height in the target reservoir.

[0087] In some possible implementations, the location of the horizontal well encountered in each segment can be determined first based on the longitudinal extension of the hydraulic fracture height; then, based on the determined location of the horizontal well encountered in each segment, the location and number of perforations in the annular horizontal wellbore section of each segment can be determined according to the longitudinal extension of the hydraulic fracture height.

[0088] According to this embodiment, based on the fracture height propagation law obtained from the simulation study in step S4, the horizontal well drilling interval can be optimized to address the uneven propagation of longitudinal fracture height. The drilling position of the horizontal well interval can be adjusted upwards or downwards according to the characteristics of uneven longitudinal fracture height propagation. After optimizing the drilled interval, further simulation studies can be conducted to investigate the fracture height propagation law in the new interval, until the horizontal well interval drilling position is continuously adjusted to maximize the balanced propagation of the fracture height in the vertically heterogeneous reservoir. Based on the optimization of the horizontal well drilling interval, the number of perforations and related parameters in the upper and lower parts of the annular horizontal wellbore section can be further optimized according to the fracture height propagation law in the new interval, promoting the uniform propagation of the fracture height in the target thick tight sandstone heterogeneous reservoir.

[0089] Back Figure 1Step S6: Based on the determined horizontal well drilling location and the location and number of perforations in the annular horizontal well section, determine the fracture parameters and well layout parameters to be used for fracturing.

[0090] The fracture parameters may include fracture length, cluster spacing, etc. The well layout parameters may include well pattern and well spacing, etc.

[0091] In some possible implementations, the horizontal well drilling location and the number and location of perforations at the annular horizontal wellbore interface in the fracturing well production capacity prediction model can be set to the determined horizontal well drilling location and the number and location of perforations at the annular horizontal wellbore interface. The fracturing well production capacity prediction model is used to predict the corresponding production capacity based on fracturing parameters and well layout parameters.

[0092] The fracture parameters and well placement parameters to be used in fracturing are determined based on the production capacity forecast results.

[0093] For example, the fracture parameters and well placement parameters of the fracturing well production capacity prediction model can be repeatedly adjusted to simulate the corresponding production capacity. Then, the fracture parameters and well placement parameters corresponding to the production capacity that best meets the expectations (e.g., the predicted maximum production capacity) are determined as the fracture parameters and well placement parameters used for fracturing.

[0094] Based on the optimized design of the horizontal well drilling location and the location and number of perforations in the annular horizontal well section mentioned above, and according to the predicted production capacity of the fracturing well, the parameters such as the fracturing fracture length, the spacing between segments and clusters, and the well network spacing are optimized to complete the geological design of the fracturing scheme for the tight and thick sandstone reservoir.

[0095] Through the above embodiments, a geological design scheme for the horizontal section of a horizontal well in thick tight sandstone is proposed, including detailed analysis of geological engineering parameters of thick tight sandstone and establishment of a fracturing model, calculation of segmented rock mechanics parameters within the layer and simulation of vertical fracture propagation, optimized design of the drilling sections encountered by the horizontal well, optimization of the perforation location distribution of the annular horizontal wellbore, and optimized design of fracturing parameters and well network spacing. According to this application, based on regional fracturing geological models and rock mechanics parameter models, the propagation law of high-fracture depth is simulated and studied. The drilling sections encountered by the horizontal well and the perforation locations of the annular horizontal wellbore are optimized to address the uneven vertical fracture depth propagation, promoting uniform propagation of high-fracture depth in thick, heterogeneous reservoirs. Based on the predicted production capacity of the fracturing well, the parameters of the fracturing fracture and well network spacing are optimized, completing the optimized design of the fracturing geological scheme for thick, tight sandstone reservoirs. The optimized fracturing geological scheme provided in this application can maximize the degree and effect of fracturing stimulation, achieve full stimulation of thick tight sandstone reservoirs, and improve oil and gas field recovery and economic benefits.

[0096] Example 2

[0097] This exemplary embodiment is illustrated by taking the optimization design of a fracturing geological scheme for a uniformly dense and thick sandstone block in Canada as an example.

[0098] (1) Comprehensive and detailed collection and analysis of geological and engineering data of the target reservoir. The target reservoir is 80m thick, a very thick tight sandstone reservoir, with a depth range of 2680m-2760m and a porosity of 3.3%-3.7%. By organizing and recording the vertical numerical changes of various parameters of the target reservoir, the heterogeneous distribution characteristics of the vertical geological and engineering parameters were clarified. Based on a full assessment of the scale of fracturing operations and the range of longitudinal and lateral reservoir modification, a regional fracturing geological model was established. Please participate. Figure 4 .

[0099] (2) The reservoir is divided into two sections: the upper section has a depth range of 2680m-2718m, and the lower section has a depth range of 2718m-2760m.

[0100] (3) Using the Anderson model, the biot coefficient was adjusted based on well logging data and geological data from different layers to calculate rock mechanics parameters such as Young's modulus, Poisson's ratio, maximum and minimum horizontal principal stresses, and fracture pressure. The following formula is for calculating the minimum horizontal principal stress:

[0101]

[0102] Where, ε y The minimum horizontal principal stress is represented by σ; Poisson's ratio is represented by P0; and overburden pressure is represented by P. p α represents the formation pore pressure; α represents the biot coefficient.

[0103] (4) Study the influence of rock mechanics parameters on fracture propagation height. Based on the regional fracturing geological model, a rock mechanics parameter model was established by interpolation. The study simulated the fracture propagation height under the condition that the horizontal well encountered a location in the middle of the reservoir and that the wellbore section was uniformly perforated. It was found that fracture height is mainly affected by the difference in minimum horizontal principal stress. Since the minimum horizontal principal stress in the lower part of the target reservoir is slightly higher than that in the upper part, please refer to [reference needed]. Figure 5 .from Figure 5 It can be seen that the fracturing fractures extend towards the upper part of the target reservoir.

[0104] (5) Based on the simulation of high propagation of the hydraulic fracture mentioned above, the drilling position of the horizontal well section was optimized. Since the hydraulic fracture height was slightly biased towards the lower part of the reservoir, the drilling position of the horizontal well section was adjusted to the lower part of the middle of the reservoir according to the simulation results of the hydraulic fracture height of different drilling sections. The horizontal well section was drilled at 2725m.

[0105] Based on the simulation results of high fracture propagation after adjusting the horizontal well drilling section, such as Figure 6 As shown, under uniform perforation conditions, the fractures have achieved essentially uniform expansion, and the annular horizontal wellbore cross-section maintains uniform perforation.

[0106] (6) Based on the optimized design of the drilling sections of horizontal wells and the perforation location of the annular horizontal well section, further optimize parameters such as fracture length, cluster spacing and well network spacing. Based on the production capacity prediction results, determine the optimal scheme and optimize the design target of 158-179m half length of fracture in tight and thick sandstone reservoir, fracture height extension through the entire reservoir to reach 80m, 3-5 clusters of fracture in a single section, cluster spacing of 18-28m, and well spacing of 400m.

[0107] Example 3

[0108] The electronic device according to embodiments of this application includes a memory and a processor.

[0109] This memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0110] The processor may be a central processing unit (CPU) or other form of processing unit with data processing and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of this application, the processor is used to run the computer-readable instructions stored in the memory to execute the horizontal geological design method for staged fracturing of a thick tight sandstone horizontal well described above.

[0111] Those skilled in the art should understand that, in order to solve the technical problem of how to achieve a good user experience, this embodiment may also include well-known structures such as communication buses and interfaces, and these well-known structures should also be included within the protection scope of this application.

[0112] For a detailed description of this embodiment, please refer to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.

[0113] Example 4

[0114] This application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the described method for segmented fracturing horizontal geological design of a thick, tight sandstone horizontal well.

[0115] A computer-readable storage medium according to embodiments of this application stores non-transitory computer-readable instructions. When these non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the methods described in the foregoing embodiments of this application are performed.

[0116] The aforementioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or portable hard drive), media with built-in rewritable non-volatile memory (e.g., memory card), and media with built-in ROM (e.g., ROM cartridge).

[0117] Example 5

[0118] This application provides a geological design device for the horizontal section of a thick, tight sandstone horizontal well with segmented fracturing, including a geological model establishment unit for the fracturing area, a layer segment division unit within the layer, a rock mechanics model establishment unit, a high vertical propagation simulation unit for fracturing fractures, a perforation design unit for drilling locations and the cross-section of the annular horizontal wellbore, and a fracturing parameter and well layout parameter determination unit.

[0119] The fracturing area geological model establishment unit is used to establish a fracturing area geological model of the target block based on the fracturing geological engineering parameters, fracturing scale and reservoir longitudinal and transverse modification range of the target area. The target area is a thick tight sandstone, and the target block is located in the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block.

[0120] The intra-layer segment division unit is used to initially divide the target block into multiple segments based on the heterogeneity of the geological and engineering characteristics of the target block.

[0121] The rock mechanics model building unit is used to build a rock mechanics model corresponding to each layer, and the rock mechanics model is used to describe the rock mechanics parameters of the corresponding layer.

[0122] The high vertical propagation simulation unit for pressure fractures is used to simulate the high vertical propagation of pressure fractures in each segment of the target block based on the geological model of the fractured area and the rock mechanics model corresponding to each segment.

[0123] The drilling location and annular horizontal wellbore section perforation design unit is used to determine the drilling location and the number of annular horizontal wellbore section perforations for each segment based on the longitudinal extension of the fracture height.

[0124] The fracturing parameter and well layout parameter determination unit is used to determine the fracture parameters and well layout parameters to be used for fracturing based on the determined horizontal well drilling locations and the location and number of perforations in the annular horizontal well section.

[0125] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A geological design method for the horizontal section of a thick, tight sandstone horizontal well undergoing segmented fracturing, characterized in that, include: Step S1: Based on the fracturing geological engineering parameters of the target area, the scale of fracturing construction and the range of longitudinal and transverse reservoir modification, establish a fracturing area geological model of the target block. The target area is a thick, tight sandstone, and the target block is located in the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block. Step S2: Based on the heterogeneity of the geological and engineering characteristics of the target block, the target block is initially divided into multiple layers; Step S3: Establish a rock mechanics model for each layer segment, wherein the rock mechanics model is used to describe the rock mechanics parameters of the corresponding layer segment; Step S4: Based on the geological model of the fracturing area and the rock mechanics model corresponding to each layer, simulate the vertical extension of the fracturing fractures in each layer of the target block; Step S5: Based on the longitudinal propagation of the hydraulic fracture, determine the horizontal well drilling location and the location and number of perforations in the annular horizontal wellbore section for each layer, wherein... The location of the horizontal well encountered in each section is determined based on the vertical extension of the hydraulic fracture. Specifically, this includes: for each section... If the resistance to the expansion of the fracture height in the upper part of the layer is large, and the fracture height expands downward, the horizontal well drilling position is set to be above the middle of the layer. If the lower part of the formation has high resistance to fracture height expansion and the fracture height expands upwards, the horizontal well drilling location should be set below the middle of the formation. If the longitudinal fracture height of the formation is uniformly extended, or the difference in resistance between the upper and lower parts of the longitudinal fracture height is small, the horizontal well drilling location is set in the middle of the formation. The location and number of perforations in the annular horizontal wellbore section of each layer are determined based on the longitudinal propagation of the hydraulic fracture, specifically including: for each layer, If the fracture height of this section extends downwards, increase the number of perforations above the annular horizontal wellbore section and decrease the number of perforations below the annular horizontal wellbore interface. If the fracture height of the segment extends upwards, increase the number of perforations below the annular horizontal wellbore section and decrease the number of perforations above the annular horizontal wellbore interface; If the fracture height of the section expands uniformly in the longitudinal direction, then perforations are evenly arranged on the cross section of the annular horizontal wellbore. Step S6: Based on the determined horizontal well drilling locations and the locations and number of perforations in the annular horizontal well section, determine the fracture parameters and well layout parameters to be used for fracturing.

2. The method according to claim 1, characterized in that, In step S3, establishing the rock mechanics model corresponding to each layer specifically includes: For each layer, based on the well logging and geological data of that layer, a rock mechanics parameter calculation model corresponding to that layer is selected, and the rock mechanics parameters of that layer are calculated to obtain the rock mechanics model corresponding to that layer.

3. The method according to any one of claims 1-2, characterized in that, In step S5, based on the longitudinal propagation of the hydraulic fracture, the location of the horizontal well drilling in each section and the location and number of perforations in the annular horizontal wellbore section are determined, specifically including: First, determine the location of the horizontal well drilling in each section based on the longitudinal extension of the fracture height; Then, based on the determined horizontal well drilling locations for each segment, and according to the longitudinal extension of the fracture height, the location and number of perforations in the annular horizontal wellbore section for each segment are determined.

4. The method according to claim 1, characterized in that, The fracture parameters include the fracture length and the spacing between segments, and the well layout parameters include the well pattern and the well spacing.

5. The method according to claim 1, characterized in that, Step S6 specifically includes: The horizontal well drilling location and the perforation location and number at the annular horizontal wellbore interface in the fracturing well production capacity prediction model are set to the determined horizontal well drilling location and the perforation location and number at the annular horizontal wellbore interface. The fracturing well production capacity prediction model is used to predict the corresponding production capacity based on fracturing parameters and well layout parameters. The fracture parameters and well placement parameters to be used in fracturing are determined based on the production capacity forecast results.

6. An electronic device, characterized in that, The electronic device includes: Memory, which stores executable instructions; A processor that executes the executable instructions in the memory to implement the geological design method for the horizontal section of a thick, tight sandstone horizontal well with segmented fracturing, as described in any one of claims 1-5.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the geological design method for the horizontal section of a thick, tight sandstone horizontal well with segmented fracturing, as described in any one of claims 1-5.

8. A geological design device for the horizontal section of a thick, tight sandstone horizontal well undergoing segmented fracturing, characterized in that, include: The fracturing area geological model establishment unit is used to establish a fracturing area geological model of the target block based on the fracturing geological engineering parameters, fracturing construction scale and reservoir longitudinal and transverse modification range of the target area. The target area is a thick tight sandstone, and the target block is located in the target area. The fracturing area geological model is used to describe multiple fracturing geological parameters of the target block. The intra-layer segment division unit is used to initially divide the target block into multiple segments based on the heterogeneity of the geological and engineering characteristics of the target block; The rock mechanics model building unit is used to build a rock mechanics model corresponding to each layer, and the rock mechanics model is used to describe the rock mechanics parameters of the corresponding layer. The high vertical propagation simulation unit for hydraulic fractures is used to simulate the high vertical propagation of hydraulic fractures in each segment of the target block based on the geological model of the hydraulic fracture area and the rock mechanics model corresponding to each segment. The drilling location and annular horizontal wellbore section perforation design unit is used to determine the drilling location and the location and number of perforations in each section of the horizontal wellbore based on the longitudinal extension of the fracture height. The location of the horizontal well encountered in each section is determined based on the vertical extension of the hydraulic fracture. Specifically, this includes: for each section... If the resistance to the expansion of the fracture height in the upper part of the layer is large, and the fracture height expands downward, the horizontal well drilling position is set to be above the middle of the layer. If the lower part of the formation has high resistance to fracture height expansion and the fracture height expands upwards, the horizontal well drilling location should be set below the middle of the formation. If the longitudinal fracture height of the formation is uniformly extended, or the difference in resistance between the upper and lower parts of the longitudinal fracture height is small, the horizontal well drilling location is set in the middle of the formation. The location and number of perforations in the annular horizontal wellbore section of each layer are determined based on the longitudinal propagation of the hydraulic fracture, specifically including: for each layer, If the fracture height of this section extends downwards, increase the number of perforations above the annular horizontal wellbore section and decrease the number of perforations below the annular horizontal wellbore interface. If the fracture height of the segment extends upwards, increase the number of perforations below the annular horizontal wellbore section and decrease the number of perforations above the annular horizontal wellbore interface; If the fracture height of the section expands uniformly in the longitudinal direction, then perforations are evenly arranged on the cross section of the annular horizontal wellbore. The fracturing parameter and well layout parameter determination unit is used to determine the fracture parameters and well layout parameters to be used for fracturing based on the determined horizontal well drilling locations and the location and number of perforations in the annular horizontal well section.

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