A method of increasing target radius in drilling

Abstract

The present application relates to the field of oil and gas field development research, and provides a method for improving target radius in drilling, comprising the following steps: step 1, determining the main layer of the target block, and determining the production capacity of the main layer; step 2, determining the sweet spot distribution of the well site deployment area based on at least the production capacity of the main layer, and determining the main layer plane and the longitudinal distribution trend of the main layer of the well site deployment area; step 3, determining the well point position based on at least the main layer plane and the longitudinal distribution trend of the main layer of the well site deployment area, and determining the well pattern; step 4, determining the target area range based on at least the well pattern, designing the target point, and designing the target point with the depth of the main layer as the target area range; and step 5, determining the directional well trajectory. The present application takes the depth of the main layer as the design target point, and considers the regular well pattern, so that the directional error of the well trajectory can be effectively reduced, the target accuracy can be improved, the well trajectory can be optimized, the footage can be further reduced, the drilling cycle can be shortened, the field operation efficiency can be improved, and the investment can be saved.

Description

Technical Field

[0001] This invention relates to the field of oil and gas field development research, and in particular to a method for increasing the target radius during drilling. Background Technology

[0002] Due to limitations imposed by surface conditions and considerations of economic efficiency, oilfield development well types are shifting from vertical wells to extended reach platform directional wells. Adopting platform directional well development reduces land occupation, saves on surface infrastructure investment, improves drilling efficiency, and allows for the control of more recoverable reserves with a minimal number of wellheads, thereby reducing the unit cost of oilfield development. Furthermore, in sensitive areas such as water source protection zones, the use of platform directional wells is beneficial for environmental protection, yielding significant economic and social benefits.

[0003] As the well structure changes from a vertical well to a platform directional well, the target point design in the existing technology is based on the middle depth of the oil layer. The completion position of the high-angle well changes the original well pattern design. The disadvantage is that it is easy to cause the risk of water flooding, water channeling or low well-controlled reserves.

[0004] CN 117313190 A discloses a method and system for designing shale gas platform well trajectories. This method first determines the key elements of single-well trajectories based on acquired geological and stratigraphic data, target depth data, and steering tool capability information, combined with 3D horizontal well trajectories design technology and drilling speed-up technology requirements. Then, based on the angle between the data of the wellhead connection line on the same side of the platform and the azimuth line of the horizontal section, a matching optimization strategy is formulated to optimize the wellhead layout. Finally, based on the optimized wellhead layout, multi-well trajectories are simultaneously implemented in a platform mode according to the key elements of single-well trajectories design. This scheme considers the optimization characteristics of multiple trajectories design elements simultaneously, ensuring the accuracy and practicality of single-well trajectories design, significantly shortening the total drilling footage while minimizing collision risks, and enabling synchronous trajectories design based on the overall platform mode, achieving synchronous construction of each well and ensuring the completion efficiency of all wells. However, this prior art does not provide a method for determining the target depth data.

[0005] Based on this, there is room for improvement in increasing the drilling target radius to enhance production and recovery. Summary of the Invention

[0006] In view of this, the present invention provides a method for increasing the target radius during drilling, which solves the problems of platform directional wells using the middle depth of the oil layer as the target point and large-angle wells changing the original well pattern at the completion position, which can easily cause water flooding, water channeling or low well-controlled reserves.

[0007] To address the aforementioned technical problems, embodiments of the present invention provide a method for increasing the target radius during drilling, comprising the following steps: Step 1: Determine the main layer of the target block and clarify the production capacity of the main phase of the main layer; Step 2: Based at least on the production capacity of the main phase zone of the main layer, determine the sweet spot distribution of the well location deployment area, and clarify the planar and longitudinal distribution trend of the main layer in the well location deployment area; Step 3: Determine the location of the well points and clarify the well network pattern based at least on the plane and longitudinal distribution trend of the main layer in the well deployment area; Step 4: At least based on the well pattern, determine the target area and design target points, with the target area designed based on the depth of the main layer. Step 5: Determine the directional well trajectory.

[0008] In some embodiments, in step 1, the main layer is identified based on the planar distribution of reservoir sedimentary microfacies, sand bodies and oil-bearing sand bodies, and the production capacity of the main facies zone of the main layer is identified in conjunction with the production dynamics.

[0009] In some embodiments, in step 2, the production capacity of the main phase zone of the main layer is utilized, and multi-parameter well-seismic combination is used to characterize the sweet spot, thereby clarifying the plane and longitudinal distribution trend of the main layer in the well location deployment area.

[0010] In some embodiments, in step 3, the well network pattern is determined by utilizing the plane of the main layer and the longitudinal distribution trend of the main layer in the well location deployment area, combined with the sweet spot characterization, based on the well-controlled reserves and the increase in recoverable reserves per well.

[0011] In some embodiments, in step 4, the well network method is used to comprehensively consider azimuth factors, displacement factors, and stratigraphic factors, and target points are designed with the depth of the main stratigraphic layer as the target area.

[0012] In some embodiments, azimuth factors, displacement factors, and formation factors refer to well trajectory azimuth factors, horizontal displacement factors, and target oil layer location factors.

[0013] In some embodiments, the main layer is the main oil layer.

[0014] In some embodiments, in step 5, the drilling encounter and well-controlled reserves of the main formation under different well trajectories are accurately predicted. Taking into account the full utilization of reserves and the maximization of economic benefits, the platform well deployment model is optimized, and a resource-based well network pattern matching sand body-well network-fracture network is constructed to obtain the directional well trajectory.

[0015] In some embodiments, in step 5, the directional well trajectory is graphically represented using a wellbore profile.

[0016] In some embodiments, in step 1, the sedimentary facies type is identified through regional sedimentary background analysis. Based on fine correlation of small layers, single-well facies, profile facies, and planar microfacies are characterized by combining core facies, seismic facies, and well logging facies. The spatial distribution pattern of different facies zones is clarified. Furthermore, based on the planar distribution map of sandstone and effective thickness contour lines of each small layer, the main layer of the well location deployment area is determined. Based on the production dynamic information of previous years, the production capacity of different facies zones is determined, and the main facies zones are selected.

[0017] In some embodiments, in step 2, planar microfacies characterization is used, and reservoir prediction maps are obtained by referring to seismic waveform indicators. Sweet spots are characterized by combining well logging interpretation and logging data from known well points, thereby clarifying the planar distribution range and distribution characteristics of effective reservoirs and the main layers in the sweet spot area.

[0018] In some embodiments, the planar distribution range and distribution characteristics of the effective reservoir and the sweet spot main layer are represented by the effective thickness contour map of the effective reservoir and the sweet spot main layer.

[0019] In some embodiments, in step 3, based on the effective thickness contour map of the effective reservoir and the main layer of the sweet spot, and combined with the sweet spot characterization, the well control reserves of the new wells and the increase in recoverable reserves of a single well are calculated according to the effective thickness of the well location deployment area and the well control area, the well network pattern is clarified, and the well location is further optimized according to the distribution of the sweet spots.

[0020] In some embodiments, in step 4, a well pattern is used to design target points with the effective reservoir depth and the main layer depth of the sweet spot as the target area range.

[0021] In some embodiments, in step 5, reservoir embedded modeling technology is used to accurately predict the thickness of the effective reservoir and the main layer of the sweet spot under different well trajectories and the well-controlled reserves. Taking into account the full utilization of reserves and the maximization of economic benefits, the platform well deployment model is optimized, and a resource-based well network pattern matching sand body-well network-fracture network is constructed to obtain the directional well trajectory.

[0022] Through the above technical solution, the method for improving the target radius in drilling provided by the present invention takes the depth of the main formation as the design target point and takes into account the regular well network. It can effectively reduce the well trajectory orientation error, improve the target accuracy, optimize the well trajectory, further reduce the footage, shorten the drilling cycle, improve the field operation efficiency, and save investment. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a flowchart of the method for increasing the target radius in drilling according to the present invention; Figure 2 This is a chart for evaluating the production capacity of different phase zones in a layered manner, as disclosed in an embodiment of the present invention. Figure 3 A chart comparing the indicators of different well pattern methods disclosed in the embodiments of the present invention; Figure 4 This is a chart showing the horizontal distances from different target centers to the top and bottom coordinates of the lower oil layer, as disclosed in the embodiments of the present invention. Figure 5 This is a three-dimensional well location deployment diagram of the optimized platform disclosed in an embodiment of the present invention. Detailed Implementation

[0025] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of the present invention by way of example, but should not be used to limit the scope of the present invention. The present invention can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0026] It should be noted that all uses of "first" and "second" in the embodiments of this invention are for the purpose of distinguishing two entities or parameters with the same name but different names. "First," "second," and similar terms do not indicate any order, quantity, or importance, but are only used to distinguish different parts. Therefore, "first" and "second" are only for convenience of expression and should not be construed as limiting the embodiments of this invention. Subsequent embodiments will not elaborate on this point. Words such as "including" or "comprising" mean that the element preceding the word covers the element listed after the word, and do not exclude the possibility of covering other elements as well.

[0027] It should be noted that, in the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0028] like Figure 1 As shown, the method for increasing the target radius in drilling provided by the present invention includes the following steps: Step 1: Determine the main layer of the target block and clarify the production capacity of the main phase of the main layer; Step 2: Based at least on the production capacity of the main phase zone of the main layer, determine the sweet spot distribution of the well location deployment area, and clarify the planar and longitudinal distribution trend of the main layer in the well location deployment area; Step 3: Determine the location of the well points and clarify the well network pattern based at least on the plane and longitudinal distribution trend of the main layer in the well deployment area; Step 4: At least based on the well pattern, determine the target area and design target points, with the target area designed based on the depth of the main layer. Step 5: Determine the directional well trajectory.

[0029] In some embodiments, in step 1, the main layer is identified based on the planar distribution of reservoir sedimentary microfacies, sand bodies and oil-bearing sand bodies, and the production capacity of the main facies zone of the main layer is identified in conjunction with the production dynamics.

[0030] Sedimentary microfacies refer to the smallest sedimentary units within a sedimentary subfacies zone that possess unique petrological, paleontological, sedimentary tectonic, and well-logging characteristics, reflecting specific sedimentary environments and hydrodynamic conditions. Sedimentary microfacies include fluvial facies, deltaic facies, lacustrine facies, and gravity-flow facies.

[0031] The main reservoir layer refers to the reservoir layer in an oil reservoir that has superior storage performance and contributes the most to oil and gas production. It is the core reservoir layer defined from the perspective of reservoir characteristics and production capacity. The main reservoir layer is characterized by good storage performance, obvious lithological advantages, high oil saturation, relatively stable distribution, and favorable fluid properties.

[0032] A facies zone refers to a region with similar sedimentary characteristics formed under specific sedimentary conditions. Different facies zones exhibit significantly different reservoir properties, and their distribution controls the distribution and accumulation of oil and gas. The dominant facies zone is the facies zone within an oil reservoir's sedimentary facies zone that plays a crucial role in oil and gas accumulation and production. Dominant facies zones can be identified through core observation, well logging analysis, and seismic interpretation. The dominant facies zone is a key component of the dominant stratigraphic layer.

[0033] Sand bodies are sandy sedimentary bodies with a specific geometric shape and distribution range. They are geological formations created by the aggregation of sand grains under specific hydrodynamic conditions during sedimentation, and are an important type of sedimentary rock. Sand bodies can provide storage space for oil and gas, form seepage channels, and control oil and gas distribution, thus influencing reservoir productivity. Oil-bearing sand bodies are sandy sedimentary bodies containing petroleum and are the main sites of oil storage in oil reservoirs. Finding and understanding the distribution and characteristics of oil-bearing sand bodies is a crucial step in oil reservoir development.

[0034] In some embodiments, in step 2, the production capacity of the main phase zone of the main layer in step 1 is utilized to perform sweet spot characterization using a combination of multi-parameter well-seismic analysis, thereby clarifying the plane and vertical distribution trend of the main layer in the well deployment area. The well deployment area is part of the target block.

[0035] Sweet spots in an oil reservoir refer to localized areas within the reservoir with exceptionally high oil and gas production potential. Sweet spots are identified by comprehensively considering various reservoir characteristics, such as porosity, permeability, and oil saturation, to determine the most favorable areas for development. They can be identified through geological analysis and geophysical methods such as well logging and seismic techniques. Sweet spot characterization refers to the precise identification and description of areas within an oil reservoir with good reservoir properties and high oil and gas production capacity using various techniques and methods. For example, by collecting and processing data including geological, well logging, and seismic data, key parameters such as reservoir physical properties and fluid properties are determined. Then, geological analysis methods, including sedimentary facies analysis and structural analysis, and / or geophysical methods, including well logging interpretation and seismic attribute analysis, are used to characterize the sweet spots.

[0036] Multi-parameter well-seismic fusion is a comprehensive geophysical exploration technique that combines well logging and seismic data, considering multiple relevant parameters, to more accurately image, describe, and analyze subsurface geological bodies, thereby effectively predicting the distribution, properties, and oil and gas distribution of subsurface reservoirs. Multi-parameter well-seismic fusion can be used for sweet spot characterization in the following ways: well-seismic calibration, which involves creating synthetic seismic records and converting well logging depth-domain data to the seismic time domain, accurately matching well logging curves with wellside seismic traces to determine the wellbore's location on the seismic profile, providing a benchmark for subsequent analysis; seismic attribute analysis, which extracts attributes such as amplitude, frequency, and phase from seismic data and establishes correlations with well logging parameters. For example, in some areas, sweet spot reservoirs with high oil saturation may exhibit high amplitude characteristics; this correlation can be used to infer the distribution range of sweet spots; and well-logged constrained seismic inversion, which uses well logging data as constraints to invert seismic data, obtaining more accurate rock physical parameters such as wave impedance. For example, by using lithology-impedance cross-analysis of wells to determine the wave impedance threshold value and identify impedance anomalies, the distribution of sweet spots can be effectively distinguished from non-sweet spots and accurately characterized. Based on the above analysis results and combined with geological background knowledge, a comprehensive study can be conducted on the geological origin and distribution patterns of sweet spots.

[0037] The main reservoir plane refers to the horizontal distribution and morphology of the main reservoir, including its planar boundaries, shape, area, and heterogeneity, such as variations in reservoir parameters like porosity, permeability, and oil saturation. The main reservoir plane can be used for: reservoir development planning, such as determining well locations; understanding the boundaries and area of ​​the main reservoir plane allows for the rational determination of well locations to maximize oil and gas reserves; planning development sequences based on reservoir characteristics differences in different areas of the main reservoir plane; reservoir dynamic monitoring, such as pressure monitoring and management; setting pressure monitoring points at different locations on the main reservoir plane to monitor pressure changes in real time; remaining oil distribution studies using various monitoring technologies (such as reservoir numerical simulation and production logging) to study the distribution patterns of remaining oil on the main reservoir plane and adjust production strategies accordingly; and reserve assessment, such as accurate reserve calculation; accurate main reservoir plane data helps improve the accuracy of reserve calculations and provides reliable reserve data for reservoir development planning. For example, in assessing development potential, the economic development value of an oil reservoir can be preliminarily determined by evaluating the main stratigraphic plane.

[0038] The vertical distribution trend of the main reservoir layer refers to the distribution pattern and variation of the main reservoir layer in the vertical direction (depth direction) of the reservoir. This trend encompasses many aspects, including variations in the thickness of the main reservoir layer, the vertical evolution of lithology, vertical variations in reservoir properties such as porosity and permeability, and contact relationships with adjacent strata. The vertical distribution trend of the main reservoir layer can be used for: reservoir description, such as constructing detailed geological models; understanding the thickness variations and lithological combinations of the main reservoir layer allows for the construction of more realistic three-dimensional reservoir geological models. For example, understanding reservoir heterogeneity helps to deepen the understanding of the vertical heterogeneity of the reservoir, which is crucial for understanding the flow patterns and distribution characteristics of fluids within the reservoir. In reservoir development, such as optimizing well location and well type design, the vertical distribution trend of the main reservoir layer is an important reference when determining the location and type of wells. For example, when formulating mining strategies and enhanced oil recovery measures, appropriate mining strategies should be developed based on the vertical distribution trend of the main strata, especially the vertical changes in reservoir properties. When implementing enhanced oil recovery measures, the vertical characteristics of the main strata also need to be considered. For reserve calculation, such as accurately estimating reserves, the thickness changes and reservoir property changes in the vertical distribution trend of the main strata directly affect the accuracy of reserve calculation.

[0039] In some embodiments, in step 3, the main layer plane and the longitudinal distribution trend of the main layer in the well location deployment area of ​​step 2 are used, combined with the sweet spot characterization, to determine the well network method based on the well-controlled reserves and the increase in recoverable reserves per well.

[0040] A well pattern refers to the arrangement of oil wells (including production and injection wells) in a planar plane during reservoir development. Well patterns are designed based on the reservoir's geological characteristics (such as oil layer distribution, permeability, and fault conditions) and development methods (such as water drive and gas drive) to effectively extract oil and gas resources. Well patterns include: regular well patterns, such as square well patterns, five-spot well patterns, seven-spot well patterns, and nine-spot well patterns; irregular well patterns, such as row well patterns and cluster well patterns; and special well patterns, such as horizontal well patterns and branching well patterns. Well patterns can effectively control reservoir areas, improve oil and gas recovery rates, balance reservoir pressure, achieve rational development methods, and guide well operations and management.

[0041] In some embodiments, in step 4, the well pattern method of step 3 is used to comprehensively consider the factors of "azimuth, displacement, and layer position," and the target point is designed with the depth of the main layer as the target area. Here, "azimuth, displacement, and layer position" refer to the well trajectory azimuth, horizontal displacement, and the location of the target oil layer. The target center can be determined through the main layer.

[0042] The depth of the main reservoir refers to the vertical distance between the top or bottom surface of the main reservoir and a reference surface (such as sea level or ground level). It is usually determined by geological analysis methods, well logging technology, and seismic exploration methods.

[0043] In some embodiments, the main layer is the main oil layer.

[0044] In some embodiments, in step 5, the drilling encounter and well-controlled reserves of the main formation under different well trajectories are accurately predicted. Taking into account the full utilization of reserves and the maximization of economic benefits, the platform well deployment model is optimized, and a resource-based well network pattern matching "sand body-well network-fracture network" is constructed to obtain the directional well trajectory.

[0045] The wellbore trajectory refers to the actual path of an oil or gas well from the wellhead to the bottom in underground space. It is a three-dimensional spatial curve, usually described by parameters such as well depth, well inclination angle, and azimuth angle. Well depth refers to the length from the wellhead to a certain measurement point; well inclination angle is the angle between the wellbore axis and the vertical line; azimuth angle is the angle between the projection of the wellbore axis onto the horizontal plane and the due north direction.

[0046] A platform well deployment model is a model used to plan the location of oil wells (including production wells and injection wells) in offshore platforms or concentrated onshore drilling areas for efficient oil and gas resource development. The platform well deployment model comprehensively considers reservoir geological factors, including reservoir boundaries and shape, distribution of major oil-bearing layers, and the influence of faults and fractures; production method factors, including injection-production balance requirements and enhanced oil recovery strategies; and surface infrastructure factors, including platform space constraints and surface pipeline connections. Platform well deployment models include center-radial models, row-column models, and hybrid models.

[0047] Fracture networks refer to the network of fractures formed by the interweaving of natural and artificial fractures in reservoir rocks. Fracture networks can improve conductivity, increase reservoir contact area, and mitigate reservoir heterogeneity in oil and gas extraction. They can be studied through microseismic monitoring, imaging logging techniques, and core analysis.

[0048] A directional well trajectory refers to the actual path of a directional well in underground space from the wellhead to the bottom. It is a three-dimensional spatial curve and is described by parameters such as the inclination angle, azimuth angle, and vertical depth (the vertical depth from the wellhead to a certain measuring point).

[0049] In some embodiments, in step 5, the directional well trajectory can be graphically represented using a wellbore profile. The wellbore profile depicts the shape of the directional well trajectory in three-dimensional space by showing the changes in parameters such as vertical depth, horizontal displacement, and well inclination angle with well depth.

[0050] Compared with existing technologies, the method of improving the target radius in drilling of the present invention uses the depth of the main formation as the design target point and takes into account the regular well network. It can effectively reduce well trajectory orientation error, improve target accuracy, optimize well trajectory, further reduce drilling footage, shorten drilling cycle, improve on-site operation efficiency, and save investment.

[0051] The present invention will be further illustrated by the following examples: The method for increasing the target radius during drilling according to the present invention includes the following steps: Step 1: Identify the main facies layer in the target block. Through regional sedimentary background analysis, clarify the sedimentary facies types. Based on detailed correlation of small layers, conduct single-well facies, profile facies, and planar microfacies characterization using a multidisciplinary approach combining core facies, seismic facies, and well logging facies to clarify the spatial distribution patterns of different facies zones. Further, based on the planar distribution maps of sandstone layers and effective thickness contour lines of each layer, determine the main facies layer in the well placement area. Based on historical production dynamics information, determine the production capacity of different facies zones and select the main facies zones. Step 2: Determine the sweet spot distribution in the well location deployment area. Using the planar microfacies characterization from Step 1, and referring to the reservoir prediction map derived from seismic waveform indication, combine the well logging interpretation and logging data from known well points to characterize the sweet spot, clarifying the planar distribution range and characteristics of the effective reservoir and the main layers in the sweet spot area, i.e., the planar distribution map of the effective thickness contour lines of the effective reservoir and the main layers in the sweet spot area. Both the effective reservoir and the main layers in the sweet spot area belong to the main layers of the well location deployment area.

[0052] Step 3: Determine the deployment well locations. Based on the effective thickness contour map of the main layer in the sweet spot area determined in Step 2, and in conjunction with the sweet spot characterization, calculate the well-controlled reserves of the new wells and the increase in recoverable reserves per well based on the effective thickness and well-controlled area of ​​the well deployment area. Clarify the well network pattern and further optimize the well locations based on the distribution of sweet spots.

[0053] Step 4: Determine the target area and design target points. Using the well pattern from Step 3, design target points within the target area, taking the effective reservoir depth and the main layer depth of the sweet spot as the target area. The target area should not change the original well pattern design, and the extension direction should avoid interference from old wells and the main flow line, with displacement controlled within a reasonable range.

[0054] Step 5: Determine the directional well trajectory. Using reservoir embedded modeling technology, accurately predict the thickness of the effective reservoir and the main layer of the sweet spot under different well trajectories, as well as the well-controlled reserves. Taking into account the full utilization of reserves and the maximization of economic benefits, optimize the platform well deployment model, construct a resource-based well network pattern that matches the sand body, well network, and fracture network, and obtain the directional well trajectory.

[0055] The application process of the method for increasing the target radius during drilling according to the present invention in a certain block of Jilin Oilfield is as follows: First, based on the sedimentary background analysis of this block, it is determined to be a shallow-water deltaic deposit. Following detailed correlation of sublayers and guided by sedimentary models, microfacies characterization of each sublayer was performed, identifying sublayer 12 as the dominant layer in this block. Based on historical data on activated layers and production dynamics, and considering the production capacity of different facies zones within each sublayer (e.g., ... Figure 2 As shown in the figure, the main body of the river channel has the strongest production capacity.

[0056] Secondly, by using the sedimentary microfacies characterization of each sublayer, sweet spot characterization is carried out in the well location deployment area in combination with seismic attributes and known well point information to clarify the planar distribution range and distribution characteristics of sublayer No. 12, namely, the planar distribution map of the effective thickness contour lines of sublayer No. 12.

[0057] Secondly, based on the contour map of the effective thickness of layer 12, and combined with the sweet spot characterization, the well-controlled reserves and the increase in recoverable reserves per well were calculated according to the effective thickness of the well deployment area and the well-controlled area. It was determined that the 250m × 10⁶m irregular inverted seven-point well pattern was the optimal configuration. Figure 3 As shown, using layer 12 as the target depth reduces the drilling depth by 35 meters compared to using the oil layer (middle of the oil layer). Furthermore, based on the distribution of sweet spots, the well location is optimized by increasing the distance between the oil wells in the east-west direction and the water wells, and decreasing the distance between the oil wells in the north-south direction and the water wells.

[0058] Secondly, using an irregular 250m×106m reverse seven-point well pattern, target points were designed with the depth of layer 12 as the target area, such as... Figure 4 As shown, the target area does not change the original well pattern design, and the extension direction avoids interference from old wells and the main line, and the displacement is controlled within a reasonable range.

[0059] Finally, using reservoir embedded modeling technology, the drilling and well-controlled reserves encountered in sub-layer 12 under different well trajectories were accurately predicted. Taking into account both maximizing reserve utilization and economic benefits, as shown in Table 1, the well profile was determined. Figure 5 As shown.

[0060] Table 1

[0061] This invention's method, by optimizing wellbore profile design and target accuracy, is particularly important for improving single-well production and block recovery. Considering the depth of the main producing layer, the designed well trajectory encounters the thickest possible oil layer in the target area while maintaining the designed well pattern, effectively reducing drilling footage. This invention's method achieves full utilization of reserves, increasing production and recovery rates.

[0062] The various embodiments of the present invention have now been described in detail. To avoid obscuring the concept of the invention, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions disclosed herein based on the above description.

[0063] While specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of the invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any manner.

Claims

1. A method for increasing the target radius during drilling, characterized in that, Includes the following steps: Step 1: Determine the main layer of the target block and clarify the production capacity of the main phase of the main layer; Step 2: Based at least on the production capacity of the main phase zone of the main layer, determine the sweet spot distribution of the well site deployment area, and clarify the planar and longitudinal distribution trends of the main layer in the well site deployment area; Step 3: Determine the location of the well points and clarify the well pattern based at least on the plane of the main layer in the well deployment area and the longitudinal distribution trend of the main layer; Step 4: Based at least on the well pattern, determine the target area and design target points, using the depth of the main layer as the target area. Step 5: Determine the directional well trajectory.

2. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 1, the main layer is identified based on the planar distribution of reservoir sedimentary microfacies, sand bodies, and oil-bearing sand bodies. Combined with production dynamics, the production capacity of the main facies zone of the main layer is determined.

3. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 2, the production capacity of the main phase zone of the main layer is used to perform sweet spot characterization by combining multi-parameter well-seismic analysis, and to clarify the planar and longitudinal distribution trend of the main layer in the well location deployment area.

4. The method for increasing the target radius in drilling according to claim 3, characterized in that, In step 3, the well network pattern is determined by utilizing the plane of the main layer and the longitudinal distribution trend of the main layer in the well location deployment area, combined with the sweet spot characterization, based on the well-controlled reserves and the increase in recoverable reserves per well.

5. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 4, the target points are designed using the well pattern method, taking into account azimuth, displacement, and stratigraphic factors, with the depth of the main stratigraphic layer as the target area range.

6. The method for increasing the target radius in drilling according to claim 5, characterized in that, The azimuth factors, displacement factors, and formation factors refer to the well trajectory azimuth factors, horizontal displacement factors, and target oil layer location factors.

7. The method for increasing the target radius in drilling according to claim 1, characterized in that, The main layer is the main oil layer.

8. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 5, the drilling of the main formation and the well-controlled reserves under different well trajectories are accurately predicted. Taking into account the full utilization of reserves and the maximization of economic benefits, the platform well deployment model is optimized, and a resource-based well network pattern matching sand body-well network-fracture network is constructed to obtain the directional well trajectory.

9. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 5, the directional well trajectory is graphically represented using a wellbore profile.

10. The method for increasing the target radius in drilling according to claim 1, characterized in that, In step 1, the sedimentary facies types are identified through regional sedimentary background analysis. Based on fine correlation of small layers, single-well facies, profile facies, and planar microfacies are characterized by combining core facies, seismic facies, and well logging facies. The spatial distribution patterns of different facies zones are clarified. Furthermore, based on the planar distribution maps of sandstone layers and effective thickness contour lines of each layer, the main layers in the well deployment area are determined. Based on the production dynamics information over the years, the production capacity of different facies zones is determined, and the main facies zones are selected.

11. The method for increasing the target radius in drilling according to claim 10, characterized in that, In step 2, the planar microfacies characterization is used, along with the reservoir prediction map obtained by referring to the seismic waveform indicator, and the sweet spot characterization is performed in combination with the well logging interpretation and logging data of known well points, so as to clarify the planar distribution range and distribution characteristics of the effective reservoir and the main layer of the sweet spot area.

12. The method for increasing the target radius in drilling according to claim 11, characterized in that, The planar distribution range and spread characteristics of the effective reservoir and the sweet spot main layer are represented by the effective thickness contour map of the effective reservoir and the sweet spot main layer.

13. The method for increasing the target radius in drilling according to claim 12, characterized in that, In step 3, based on the effective thickness contour map of the effective reservoir and the main layer of the sweet spot, and combined with the sweet spot characterization, the well control reserves of the new wells and the increase in recoverable reserves of a single well are calculated according to the effective thickness of the well location deployment area and the well control area. The well network method is clarified, and the well point location is further optimized according to the distribution of the sweet spot.

14. The method for increasing the target radius in drilling according to claim 13, characterized in that, In step 4, the target points are designed using the well pattern to define the target area range based on the effective reservoir depth and the main layer depth of the sweet spot.

15. The method for increasing the target radius in drilling according to claim 14, characterized in that, In step 5, reservoir embedded modeling technology is used to accurately predict the drilling thickness and well-controlled reserves of the effective reservoir and sweet spot main layer under different well trajectories. Taking into account the full utilization of reserves and the maximization of economic benefits, the platform well deployment model is optimized, and a resource-based well network pattern matching sand body-well network-fracture network is constructed to obtain the directional well trajectory.

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