Well position and well trajectory determination, well drilling speed increasing and transformation yield increasing method

Abstract

The invention provides a well position and well trajectory determination, well drilling speed increase and transformation yield increase method, and belongs to the field of deep ground oil and gas resource exploration and development, the well trajectory determination method comprises the following steps: establishing a full-strata-series three-dimensional rock mechanical parameter field model according to a formation pressure test and flow phase constraints of each stratum, and obtaining full-strata-series rock mechanical parameters; according to the geological structure and the formation pressure field of each stratum, establishing a three-dimensional full-strata-series stress field prediction model, and obtaining full-strata-series three-dimensional stress field parameters; according to the full-strata rock mechanical parameters, the full-strata three-dimensional stress field parameters and the three-dimensional natural fracture model, a natural fracture activity prediction model is established, and fracture activity is evaluated; and determining a well location and a well trajectory according to the three-dimensional current ground stress model, the three-dimensional fracturing performance prediction model and the fracture activity and three-dimensional collapse pressure prediction model. Through the method provided by the invention, the effects of well drilling speed increase and transformation yield increase can be achieved in most complex oil and gas field blocks.

Description

Technical Field

[0001] The present invention relates to the technical field of deep-earth oil and gas resource exploration and development, and in particular to a method for determining a well location and trajectory, a method for increasing drilling speed, and a method for increasing production through transformation. Background Art

[0002] Geomechanical parameters are one of the important factors affecting oil and gas exploration results, reservoir transformation effects, fracturing construction effects, and other oilfield drilling and completion engineering and oil and gas reservoir engineering, and they play an important role and significance in petroleum engineering. In actual oil and gas field production, geomechanical parameters play a very important role in the entire life cycle of oil and gas reservoir exploration and development. If we can comprehensively apply the geological, logging, geophysical, drilling, testing, fracturing and other data in the oil and gas field area and wellbore on the basis of geological knowledge and engineering practice to establish a geomechanical parameter model that meets the needs of oil and gas field production, and evaluate the geomechanical characteristics of oil and gas fields based on the geomechanical parameter model, and apply the geomechanical characteristics of oil and gas fields to the entire life cycle of oil and gas reservoir exploration and development, including closure prediction, well site deployment, drilling engineering, tracking while drilling, completion transformation, development plan and gas storage construction, it will help solve the problems related to reservoir quality evaluation, well site and trajectory optimization, safe and rapid drilling, completion and efficient production increase, and generate greater economic benefits.

[0003] However, most of the current research directions on geomechanical parameters focus on determining the mechanical properties of geological materials and their relationship with geological structure and stress state, so as to study and analyze the structural characteristics of various levels and the distribution law of structural units in order to guide the relevant work of oil and gas exploration and development, but have not yet solved the specific production problems in oil and gas exploration and development. For example, in the process of oil and gas exploration and development, the existing geomechanical characteristic evaluation methods generally focus on rock mechanics experiments of deep rock samples, build parameter calculation models based on rock mechanics experiments, and use logging data to quantitatively evaluate the one-dimensional rock mechanics parameter characteristics of the wellbore. In this evaluation process, the mechanical characteristics can only be inverted from the local rock scale, and the comprehensive mechanical properties cannot be inverted from the perspective of oil and gas reservoirs and special formation geological bodies, nor can the influence of fractures and natural fractures on rock mechanics be inverted. It is even more difficult to realize the geomechanical characteristic analysis within the three-dimensional scale of oil and gas fields, and it cannot effectively solve the engineering geological problems faced by oil and gas exploration and development.

[0004] In addition, although some scholars have tried to evaluate the geological parameters of oil and gas fields and apply the geomechanical characteristics obtained from the evaluation to drilling speed-up and completion transformation to increase production, they mainly focus on the application of one aspect of technology and have not achieved good results in speed-up and production increase. For example, in drilling speed-up, the existing technology mainly considers the influence of geomechanical characteristics in the process of predicting formation pore pressure, and does not fully consider that geomechanical characteristics will also have a certain impact on the prediction of wellbore stability of various different lithologies. Therefore, when geomechanical characteristics are applied in drilling speed-up, serious wellbore instability usually occurs, affecting the speed-up effect. In completion transformation to increase production, the existing technology only determines the geomechanical characteristics through the wellbore rock physical parameters and optimizes the completion transformation process. It does not fully consider the influence of the distribution of natural fractures and the distribution of the reservoir around the well on the geomechanical characteristics, resulting in unsatisfactory transformation and production increase effects.

[0005] In summary, from a comprehensive perspective, the factors considered by traditional technologies for speeding up and increasing production in oil and gas fields are relatively single. In most cases, they are considered from the perspectives of geological research and geophysics, without fully considering the impact of geostress, rock mechanics and fracture mechanics on drilling speed-up and completion production increase, resulting in the speed-up and production increase effect not meeting expectations. In addition, the prerequisite for drilling speed-up and production increase is the accurate selection of well locations and the reasonable design of well trajectories. Traditional technologies have not formed an integrated solution idea, considering the source, considering well trajectory optimization, drilling speed-up and completion production increase as a complete production process, and applying oil and gas field geomechanics research one by one at each node in the production process to achieve transformation and substantial production increase, thereby achieving the ultimate goal of efficient development of complex oil and gas reservoirs. Summary of the invention

[0006] In view of the technical problem that the existing technology has not yet integrated the research on oil and gas field geomechanics into production processes such as well trajectory optimization, drilling speed-up, and completion and production increase, and cannot achieve efficient development of complex oil and gas reservoirs, the present invention provides a method for determining well location and well trajectory, which can obtain the best well location and well trajectory in the target area through the evaluation results of geomechanical characteristics within the scope of complex oil and gas fields, and provide a good foundation for subsequent drilling speed-up and completion and production increase. The present invention also provides a method for speeding up drilling, which can be used to obtain optimized drilling parameters and implement drilling after drilling according to the best well location and well trajectory determined by the above-mentioned method for determining well location and well trajectory, thereby achieving the goal of increasing drilling speed. The present invention also provides a method for transformation and production increase, which can optimize completion and transformation parameters through geomechanical research after completion, achieve a significant increase in transformation, and thus achieve the ultimate goal of efficient development of complex oil and gas reservoirs.

[0007] To achieve the above-mentioned objectives, the first aspect of the present invention provides a method for determining a well location and a well trajectory, the method comprising the following steps: establishing a three-dimensional rock mechanics parameter field model for the entire formation system according to formation pressure tests and flow phase constraints of each formation, and obtaining rock mechanics parameters for the entire formation system; establishing a three-dimensional stress field prediction model for the entire formation system according to the geological structure and the formation pressure field of each formation, and obtaining three-dimensional stress field parameters for the entire formation system; establishing a natural fracture activity prediction model according to the rock mechanics parameters for the entire formation system, the three-dimensional stress field parameters for the entire formation system, and a three-dimensional natural fracture model, and evaluating fracture activity; determining the well location according to a three-dimensional current geostress model, a three-dimensional fracturing prediction model, and a fracture activity; and determining the well trajectory according to fracture activity, a three-dimensional fracturing prediction model, a three-dimensional current geostress model, and a three-dimensional collapse pressure prediction model.

[0008] In an exemplary embodiment of the present invention, the three-dimensional rock mechanical parameter field model of the whole formation is established according to the formation pressure test and the flow phase constraints of each formation, and the rock mechanical parameters of the whole formation are obtained, which may include: establishing a three-dimensional structural framework model of the whole formation from the ground to the target layer based on the structural interpretation and geological stratification comparison data; establishing the sedimentary phase / lithological phase model of each formation in the target area according to the three-dimensional structural framework model of the whole formation, logging data and logging interpretation results; establishing a rock physical parameter field model of the whole formation with the sedimentary phase or lithofacies model as constraints; establishing a three-dimensional rock mechanical parameter field model of the whole formation according to the rock physical parameter field model of the whole formation, formation pressure test and the flow phase constraints of each formation from the ground.

[0009] In an exemplary embodiment of the present invention, the full-stratum rock physical parameter field model may include: sedimentary phase / lithological phase parameter model, porosity parameter model, density parameter model; the full-stratum rock mechanical parameter model may include: Young's modulus, Poisson's ratio, and compressive strength.

[0010] In an exemplary embodiment of the present invention, the three-dimensional rock mechanical parameter field model of the entire formation is established based on the formation pressure test and the flow phase constraints of each formation to obtain the rock mechanical parameters of the entire formation, and it can also include: before the rock physical parameter field model of the entire formation is established with the sedimentary phase or lithofacies model as a constraint, the sedimentary phase model or the lithofacies model is selected according to the rock mechanics experimental results and the one-dimensional rock mechanics parameter interpretation results.

[0011] In an exemplary embodiment of the present invention, establishing a three-dimensional stress field prediction model for the entire formation system based on the geological structure and the formation pressure field of each formation, and obtaining the three-dimensional stress field parameters of the entire formation system may include: establishing the formation pressure field of each formation; setting boundary conditions according to the strength of the tectonic stress background in the target area, and establishing the three-dimensional stress field parameters of the entire formation system using a finite element numerical simulation method.

[0012] In an exemplary embodiment of the present invention, the method for determining the well location and well trajectory may also include: evaluating the formation pressure of each layer, and comparing the evaluation results with the three-dimensional stress field parameters of the entire layer system. If the accuracy requirements are not met, resetting the boundary conditions and performing finite element numerical simulation calculations again.

[0013] In an exemplary embodiment of the present invention, the three-dimensional stress field parameters of the whole layer system may include: vertical stress, horizontal maximum principal stress, horizontal minimum principal stress, and principal stress direction; the natural fracture activity prediction model is established according to the rock mechanics parameters of the whole layer system, the three-dimensional stress field parameters of the whole layer system, and the three-dimensional natural fracture model to evaluate the fracture activity, which may include: collecting each of the three-dimensional stress field parameters of the whole layer system to each fracture of the three-dimensional natural fracture model; calculating the effective normal stress σ of each fracture Ne and shear stress τ, according to the shear stress τ and the effective normal stress σ Ne The ratio of is used to evaluate the fracture activity.

[0014] In an exemplary embodiment of the present invention, the effective normal stress σ Ne It can be obtained by the following formula: (Formula 1)

[0015] The shear stress τ is obtained by the following formula: (Formula 2)

[0016] Among them, l = cos(θ), m = sin(θ)sin(φ-γ), n = sin(θ)cos(φ-γ); θ is the crack inclination; φ is the crack dip; γ is the angle between the maximum horizontal principal stress and the north direction; σ 1 is the stress with the largest stress value among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 2 is the stress in the middle of the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 3 It is the smallest stress among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress.

[0017] In an exemplary embodiment of the present invention, the three-dimensional natural fracture prediction model can be obtained by the following method: establishing a three-dimensional natural fracture DFN model of the target area according to the distribution trend of the fractures; correcting the three-dimensional natural fracture DFN model through the single well fracture interpretation results to form the three-dimensional natural fracture prediction model.

[0018] In an exemplary embodiment of the present invention, establishing a three-dimensional natural fracture DFN model of the target area based on the distribution trend of the fractures may include: obtaining the single well fracture type according to the fracture interpretation results, the geological and structural regional background laws and the core fracture description results, dividing the fault-derived fractures and the fractures related to fold deformation, and analyzing the occurrence parameters of various types of fractures; and predicting the distribution trends of fault-related fractures and fold-related fractures respectively.

[0019] In an exemplary embodiment of the present invention, the prediction of the distribution trends of fault-related cracks and fold-related cracks respectively may include: for fault-related cracks: obtaining the distribution range of fault-derived cracks through three-dimensional fault recovery calculation, and obtaining the distribution trend of all fault-derived cracks in the study area through calculation of the fault distance; for fold-related cracks: obtaining the size of structural deformation through fold recovery calculation in order to analyze the distribution of cracks caused by structural deformation; obtaining the distribution trend of cracks generated by all strata in the study area during the fold deformation process through calculation of fold deformation.

[0020] In an exemplary embodiment of the present invention, the determining of the well location according to the three-dimensional current geostress model, the three-dimensional fracturability prediction model and the fracture activity may include: determining the well location according to the three-dimensional current geostress model, the three-dimensional fracturability prediction model and the natural fracture activity prediction model, preferably in a target layer with weak stress, and an area of ​​the target layer with good fracture activity and high fracturability.

[0021] In an exemplary embodiment of the present invention, the method of determining the well trajectory according to the fracture activity, the three-dimensional fracturability prediction model, the three-dimensional current geostress model and the three-dimensional collapse pressure prediction model may include: according to the three-dimensional current geostress model, the three-dimensional fracturability prediction model, the natural fracture activity prediction model and the three-dimensional collapse pressure prediction model, preferably drilling a well trajectory that encounters the most natural fractures, has high formation fracturability and high formation collapse pressure.

[0022] In an exemplary embodiment of the present invention, the three-dimensional current geostress model can be obtained in the following manner: evaluating the rock mechanical parameters according to the logging data, establishing a one-dimensional geomechanical model, and evaluating the formation pore pressure; performing joint well-seismic inversion to obtain a three-dimensional spatial wave impedance attribute body of the entire formation; converting the wave impedance body into longitudinal wave, density, transverse wave and formation mud content data according to the relationship between longitudinal and transverse waves and density established by drilling; predicting the formation pressure according to the longitudinal wave, density, transverse wave and formation mud content to obtain formation pressure prediction data; and forming the three-dimensional current geostress model of pressure distribution in three dimensions according to the formation pressure prediction data and the wellbore stability of different lithology formations in the entire wellbore.

[0023] In an exemplary embodiment of the present invention, the formation pressure may include formation pore pressure, formation collapse pressure, formation fracture pressure, leakage pressure, and closure pressure; the formation pore pressure is predicted using a nonlinear trend line method for sandstone and / or a multi-rock physical fitting method for carbonate rock; the formation collapse pressure and the formation fracture pressure are predicted using the Mohr-Coulomb theory.

[0024] In an exemplary embodiment of the present invention, the three-dimensional present-day geostress model may be corrected using the coring data and the measured data to obtain a corrected three-dimensional present-day geostress model.

[0025] In an exemplary embodiment of the present invention, the three-dimensional fracturability prediction model can be obtained in the following manner: a one-dimensional geomechanical model is established based on logging data and rock mechanical parameters of the target layer to obtain the current ground stress profile; the pressure at which shear slip occurs in the natural fractures is obtained based on the natural fracture information of the wellbore and the current ground stress profile obtained from the imaging logging data; a formation fracturability model is established based on the rock brittleness, toughness, ground stress and the pressure at which shear slip occurs in the natural fractures; and a three-dimensional fracturability prediction model is established based on the formation fracturability model.

[0026] A second aspect of the present invention provides a method for increasing drilling speed, wherein drilling is performed using the well location and well trajectory determined by the well location and well trajectory determination method described above.

[0027] The third aspect of the present invention provides a method for transformation and production increase, which comprises: drilling a well using the well location and well trajectory determined by the well location and well trajectory determination method described above; after drilling, obtaining a fracturing profile based on a formation fracturing model, dividing the wellbore longitudinal reservoir completion quality evaluation, and transforming the reservoir based on the evaluation results.

[0028] In another exemplary embodiment of the present invention, obtaining a fracability profile based on a formation fracability model and dividing the wellbore longitudinal reservoir completion quality evaluation may include: establishing a formation fracability model based on rock brittleness, toughness, geostress and the pressure of shear slip in natural fractures; obtaining a fracability profile based on the formation fracability model; and dividing the wellbore longitudinal reservoir completion quality evaluation based on the fracability profile.

[0029] In another exemplary embodiment of the present invention, the pressure at which shear slip occurs in the natural fracture can be obtained in the following manner: evaluating the rock mechanical parameters based on the logging data, establishing a one-dimensional geomechanical model, and obtaining the current ground stress profile; analyzing the force on the natural fractures in the wellbore based on the natural fracture information and the current ground stress profile obtained from the imaging logging data, and obtaining the pressure at which shear slip occurs in the natural fracture.

[0030] Through the technical solution provided by the present invention, the present invention has at least the following technical effects: (1) The method for determining the well location and trajectory of the present invention combines geological structure modeling, well-seismic combined geophysical technology and deep rock mechanics research to innovatively form a comprehensive evaluation system for the geomechanical parameter field of oil and gas fields. The comprehensive evaluation results can be applied to the well trajectory design, realizing the accurate selection of well locations and the reasonable design of well trajectories, forming the prerequisite for increasing drilling speed and production; (2) The drilling speed-up method of the present invention applies the comprehensive evaluation results of oil and gas field geomechanical parameters to the drilling speed-up, fully considers the influence of the wellbore stability of different lithologies on the speed-up effect, and achieves the goal of increasing the drilling speed by optimizing the drilling parameters; (3) The transformation and production increase method of the present invention applies the comprehensive evaluation results of the geomechanical parameters of the oil and gas field to the completion and production increase, fully considering the influence of the ground stress, rock mechanics and fracture and crack mechanical properties on the completion and production increase, and by optimizing the completion and transformation parameters, the transformation and production increase can be greatly increased, thereby achieving the ultimate goal of efficient development of complex oil and gas reservoirs; (4) The present invention starts from the geological nature and the source of reservoir quality, determines the comprehensive evaluation results of the geomechanical parameters of the oil and gas field, and applies the comprehensive evaluation results of the geomechanical parameters of the oil and gas field to the specific production processes such as well site selection, well trajectory planning, drilling speed increase, and fracturing and production increase in the oil and gas field drilling and completion engineering, thus forming an integrated solution. It can not only optimize the specific production processes in the oil field drilling and completion engineering and oil and gas reservoir engineering, but also take into account all factors, and can achieve certain transformation and production increase effects in most complex oil and gas field blocks, and has the conditions for wide promotion; (5) The present invention will promote the deepening of geological knowledge of ultra-deep oil and gas reservoirs, enrich the ultra-deep petroleum geological theory, and directly improve the accuracy of ultra-deep reservoir quality evaluation and prediction; (6) The present invention will effectively promote the advancement of geological and engineering integrated technology and solve some engineering geological problems related to safety, speed-up and production increase in ultra-deep drilling and completion projects; (7) The present invention will greatly improve the benefits of exploration and development of ultra-deep and complex oil and gas resources, while effectively reducing the safety, cost and long-term risks and uncertainties faced in exploration and development.

[0031] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings: Figure 1A flow chart of a comprehensive evaluation method for geomechanical parameters of oil and gas fields provided by an embodiment of the present invention; Figure 2 A technical flow chart of full-layer three-dimensional geostress field modeling provided by an embodiment of the present invention; Figure 3 A technical flow chart of rock mechanics experiments of different lithology formations provided by an embodiment of the present invention; Figure 4 A technical flow chart for predicting three-dimensional natural fractures and their activity provided by an embodiment of the present invention; Figure 5 A technical flow chart of well location and trajectory optimization provided by an embodiment of the present invention; Figure 6 A technical flow chart of drilling speed optimization provided by an embodiment of the present invention; Figure 7 A schematic diagram of a drilling speed-up optimization result provided by an embodiment of the present invention; Figure 8 A schematic diagram of a well completion modification and production increase method provided by an embodiment of the present invention; Fig. 9 A schematic diagram of a three-dimensional stress field model of Keshen 10 provided in an embodiment of the present invention; Fig.10 A schematic diagram of a wellbore stability analysis of a simulated vertical well and a highly deviated well provided by an embodiment of the present invention; Fig.11 A schematic diagram of the natural fracture orientation of the Keshen 10 wellbore provided in an embodiment of the present invention; Fig.12 A schematic diagram of the natural fracture inclination angle of the Keshen 10 wellbore provided in an embodiment of the present invention; Fig.13 A schematic diagram of crack opening rates under different injection pressures provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0036] Embodiment 1 Please refer to Figure 1 The first embodiment of the present invention provides a method for determining a well location and a well trajectory, the method comprising the following steps: Step S101: According to the formation pressure test and the flow phase constraints of each formation, a three-dimensional rock mechanics parameter field model of the entire formation is established to obtain the rock mechanics parameters of the entire formation.

[0037] Step S102: According to the geological structure and the formation pressure field of each formation, a three-dimensional stress field prediction model for the entire formation is established to obtain the three-dimensional stress field parameters for the entire formation.

[0038] Step S103: Establish a natural fracture activity prediction model based on the rock mechanics parameters of the entire layer system, the three-dimensional stress field parameters of the entire layer system and the three-dimensional natural fracture model to evaluate the fracture activity.

[0039] Step S104: Determine the well location based on the three-dimensional current geostress model, the three-dimensional fracturability prediction model and the fracture activity.

[0040] Step S105: determining the well trajectory according to the fracture activity, the three-dimensional fracturability prediction model, the three-dimensional current geostress model and the three-dimensional collapse pressure prediction model.

[0041] Further, in a possible implementation, in step S101, a three-dimensional rock mechanics parameter field model of the entire formation is established according to the formation pressure test and the flow phase constraints of each formation. The process of obtaining the rock mechanics parameters of the entire formation may include but is not limited to the following sub-steps S1011 to S1014 (such as Figure 2 as shown).

[0042] Sub-step S1011: Based on the structural interpretation and geological stratification comparison data, a three-dimensional structural framework model of the entire layer from the ground to the target layer is established.

[0043] Here, it should be noted that the structural interpretation data should at least include the structural interpretation results from the ground to the target layer and the structural interpretation results of the faults.

[0044] The three-dimensional structural framework model of the entire stratum system should include stratigraphic models and fault models of each stratum to reflect the three-dimensional distribution characteristics of strata and faults in the study area.

[0045] Sub-step S1012: Establish sedimentary facies / lithological facies models of each stratum in the target area based on the three-dimensional structural framework model of the entire stratum system, logging data and logging interpretation results.

[0046] Sub-step S1013: Establishing a full-layer rock physical parameter field model with the sedimentary facies model or lithofacies model as a constraint.

[0047] Here, it should be noted that the full-layer rock physical parameter field model may include: sedimentary phase / lithological phase parameter model, porosity parameter model, and density parameter model.

[0048] Sub-step S1014: Establish a three-dimensional rock mechanics parameter field model for the entire formation according to the rock physical parameter field model for the entire formation, formation pressure testing, and flow phase constraints of each formation from the ground.

[0049] Here, it should be noted that the full-layer rock mechanics parameter model can include: Young's modulus, Poisson's ratio and compressive strength.

[0050] Furthermore, in a possible implementation, before sub-step S1013, a sedimentary phase model or a lithofacies model may be selected based on rock mechanics experimental results and one-dimensional rock mechanics parameter interpretation results.

[0051] For example, different types of rock mechanics experiments are carried out on different lithology geological bodies to obtain rock mechanics experimental results of different lithology geological bodies.

[0052] Among them, different lithological geological bodies include sandstone layers, mudstone, gypsum, salt rock, dense sandstone, fractured sandstone, coal and carbonate rock.

[0053] Different types of rock mechanics experiments include uniaxial rock mechanics experiments at different temperatures, triaxial rock mechanics experiments at different temperatures, uniaxial rock mechanics experiments under different fluids, triaxial rock mechanics experiments under different fluids, uniaxial rock mechanics experiments at different loading rates, and triaxial rock mechanics experiments at different loading rates.

[0054] Taking the Tarim Basin as an example, the strata in the Tarim Basin are fully developed, from the Quaternary to the Nanhua System. In order to clarify the rock mechanical properties of different lithological geological bodies and their impact on reservoirs and engineering, different types of rock mechanics experiments need to be carried out. Figure 3 As shown in the figure, the typical lithologies in the Tarim Basin include gravel layers, mudstones, gypsum salt, salt rock, tight sandstone, fractured sandstone, coal-bearing strata and carbonate rocks. Since rocks are the product of geological action, their geological nature, i.e., materiality, structure, occurrence and evolution, must be considered when analyzing the mechanical properties of rocks, including mineral composition, structural characteristics, confining pressure, temperature and fluid conditions. Based on this, before conducting various rock mechanics experiments, it is necessary to clarify their mineral composition and structural characteristics through XRD and thin section analysis, and use CT scanning and three-dimensional reconstruction technology to intuitively display the full information of the rock. Then, uniaxial / triaxial rock mechanics experiments are carried out at different temperatures, fluids and different loading rates, and mechanical experiments with repeated loading are carried out as needed, so as to systematically analyze the rock mechanical properties and provide basic data for the study of rock fracture mechanism.

[0055] Further, in a possible implementation, in step S102, a three-dimensional full-layer stress field prediction model is established according to the geological structure and the formation pressure field of each layer, and the process of obtaining the three-dimensional stress field parameters of the full-layer system may include but is not limited to the following sub-steps S1021 to S1022 (such as Figure 2 as shown).

[0056] Sub-step S1021: Establishing the formation pressure field of each formation.

[0057] Sub-step S1022: setting boundary conditions according to the strength of the tectonic stress background in the target area, and establishing the three-dimensional stress field parameters of the entire layer system using the finite element numerical simulation method.

[0058] Here, it should be noted that the three-dimensional stress field parameters of the entire layer system include: vertical stress, horizontal maximum principal stress, horizontal minimum principal stress and principal stress direction.

[0059] Furthermore, in a possible implementation manner, a three-dimensional full-layer system stress field prediction model is established based on the geological structure and the formation pressure field of each formation. The process of obtaining the three-dimensional stress field parameters of the full-layer system may also include step S1023: evaluating the formation pressure of each layer, and comparing the evaluation results with the three-dimensional stress field parameters of the full-layer system. If the accuracy requirements are not met, the boundary conditions are reset and the finite element numerical simulation calculation is performed again.

[0060] Furthermore, in a possible implementation, in step S103, a natural fracture activity prediction model is established based on the rock mechanics parameters of the entire formation, the three-dimensional stress field parameters of the entire formation, and the three-dimensional natural fracture model. The process of evaluating fracture activity may include but is not limited to the following sub-steps S1031 to S1032.

[0061] Sub-step S1031: collecting the three-dimensional stress field parameters of the entire layer system to each fracture of the three-dimensional natural fracture model.

[0062] Here, it should be noted that the three-dimensional stress field parameters of the entire layer system may include: vertical stress, maximum horizontal principal stress, minimum horizontal principal stress and principal stress direction.

[0063] Sub-step S1032: Calculate the effective normal stress σ of each crack Ne and shear stress τ, according to the shear stress τ and the effective normal stress σ Ne The ratio of is used to evaluate the fracture activity.

[0064] Furthermore, in a possible implementation, the effective normal stress σ Ne Obtained by the following formula: (Formula 1)

[0065] The shear stress τ is obtained by the following formula: (Formula 2)

[0066] Among them, l = cos(θ), m = sin(θ)sin(φ-γ), n = sin(θ)cos(φ-γ); θ is the crack inclination; φ is the crack dip; γ is the angle between the maximum horizontal principal stress and the north direction; σ 1 is the stress with the largest stress value among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 2 is the stress in the middle of the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 3 It is the smallest stress among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress.

[0067] Further, in a possible implementation manner, in sub-step S1031, the three-dimensional natural fracture prediction model can be obtained by the following method (eg Figure 4 shown): Sub-step S10311: Establish a three-dimensional natural fracture DFN model of the target area based on the distribution trend of the fractures.

[0068] Sub-step S10312: Correcting the three-dimensional natural fracture DFN model through the single well fracture interpretation results to form the three-dimensional natural fracture prediction model.

[0069] Further, in a possible implementation, in sub-step S10311, the process of establishing a three-dimensional natural fracture DFN model of the target area according to the distribution trend of the fractures may include but is not limited to the following sub-steps S103111 to S103112 (such as Figure 4 as shown).

[0070] Sub-step S103111: According to the fracture interpretation results, geological and structural regional background laws and core fracture description results, the single well fracture type is obtained, fault-derived fractures and fractures related to fold deformation are divided, and the occurrence parameters of various fractures are analyzed.

[0071] Sub-step S103112: predict the distribution trends of fault-related cracks and fold-related cracks respectively.

[0072] Further, in a possible implementation manner, in sub-step S103112, the process of predicting the distribution trends of fault-related cracks and fold-related cracks can be implemented in the following manner (eg Figure 4 as shown).

[0073] (a) For fault-related cracks: The distribution range of fault-derived cracks is obtained through three-dimensional fault throw recovery calculation, and the distribution trend of all fault-derived cracks in the study area is obtained by calculating the fault throw size.

[0074] (b) For fold-related cracks: Through fold recovery calculation, the magnitude of structural deformation is obtained in order to analyze the distribution of cracks caused by structural deformation; through the calculation of fold deformation, the distribution trend of cracks generated in all strata in the study area during the fold deformation process is obtained.

[0075] Further, in a possible implementation, in step S104, the process of determining the well location according to the three-dimensional current geostress model, the three-dimensional fracturability prediction model and the fracture activity can be implemented in the following manner (eg Figure 5 shown): Based on the three-dimensional current geostress model, the three-dimensional fracturability prediction model, and the natural fracture activity prediction model, the well location is preferably determined in the target layer with weak stress and the area with good fracture activity and high fracturability of the target layer.

[0076] Further, in a possible implementation manner, in step S105, the process of determining the well trajectory according to the fracture activity, the three-dimensional fracturability prediction model, the three-dimensional current geostress model and the three-dimensional collapse pressure prediction model can be implemented in the following manner (e.g. Figure 5 shown): According to the three-dimensional current geostress model, the three-dimensional fracturability prediction model, the natural fracture activity prediction model and the three-dimensional collapse pressure prediction model, the well trajectory that encounters the most natural fractures, has high formation fracturability and high formation collapse pressure is preferably drilled.

[0077] Further, in a possible implementation manner, the three-dimensional current geostress model in step S104 is obtained by: (1) Evaluate the rock mechanical parameters based on the logging data, establish a one-dimensional geomechanical model, and evaluate the formation pore pressure; (2) Perform joint well-seismic inversion to obtain the three-dimensional wave impedance attribute volume of the entire formation; (3) Based on the relationship between P-wave and S-wave and density established in the drilling process, the wave impedance body is converted into P-wave, density, S-wave and formation mud content data; (4) Predict formation pressure based on P-wave, density, S-wave and formation mud content to obtain formation pressure prediction data; (5) Based on the predicted data of formation pressure and the wellbore stability of different lithology formations in the entire wellbore, the three-dimensional current ground stress model including the pressure distribution in three-dimensional space is formed.

[0078] Here, it should be noted that the formation pressure described in the present invention includes: formation pore pressure, formation collapse pressure, formation fracture pressure, leakage pressure and closure pressure. Among them, the formation pore pressure can be predicted by the nonlinear trend line method for sandstone and mudstone and / or the multi-rock physical fitting method for carbonate rock. The formation collapse pressure and formation fracture pressure can be predicted by the Mohr-Coulomb theory.

[0079] The three-dimensional current geostress model covers the pressure distribution in three-dimensional space and can be used to characterize the regional laws of wellbore stability.

[0080] In addition, the three-dimensional current geostress model can be corrected using the coring data and the measured data to obtain a corrected three-dimensional current geostress model.

[0081] Further, in a possible implementation manner, the three-dimensional fracturability prediction model in step S104 can be obtained in the following manner: (1) Based on the well logging data and the rock mechanical parameters of the target layer, a one-dimensional geomechanical model is established to obtain the current geostress profile; (2) Based on the natural fracture information of the wellbore and the current ground stress profile obtained from the imaging logging data, the pressure at which shear slip occurs in the natural fracture is obtained; (3) Establish a formation fracturability model based on rock brittleness, toughness, geostress, and shear slip pressure of natural fractures; (4) Establish a three-dimensional fracturing prediction model based on the formation fracturing model.

[0082] Embodiment 2 A second embodiment of the present invention provides a method for increasing drilling speed, which uses the well location and well trajectory determined by the well location and well trajectory determination method described in the first embodiment to perform drilling.

[0083] Specifically, when deploying wells, the area with weak stress, good fracture activity and high fracturing ability in the target layer can be selected as the optimal well location based on the three-dimensional current geostress model, the natural fracture activity prediction model and the three-dimensional fracturing ability prediction model.

[0084] When drilling, it is possible to prioritize drilling in formations with high collapse pressure based on the three-dimensional collapse pressure prediction model and wellbore stability requirements.

[0085] When determining the well trajectory, the three-dimensional fracture activity model, the three-dimensional fracturing ability prediction model and the three-dimensional collapse pressure prediction model can be combined to preferably select the well trajectory that encounters the most natural fractures, has high formation fracturing ability and high formation collapse pressure as the comprehensive optimal well trajectory.

[0086] By combining the optimal well location and the best well trajectory, the best well location and trajectory optimization can be formed which comprehensively considers the wellbore stability, drilling cracks and the benefits for later transformation.

[0087] In addition, during the drilling process, the formation pressure prediction data obtained by the method for determining the well position and well trajectory of the first embodiment can be used to optimize the drilling fluid density window and drilling fluid performance indicators, and at the same time determine the wellbore structure design and the pressure level design of the well control equipment (such as Figure 6 as shown).

[0088] For example, Figure 7 The schematic diagram of the drilling speed optimization result is as follows: Figure 7 As shown, it can be seen that there are four main pressure systems in the vertical direction of the well, namely: ① The surface-upper formation of the Jidike Formation is at normal pressure; ② The pore pressure coefficient of the middle and lower formations of the Jidike Formation gradually increases, and the pressure rises to 1.6 in the Paleogene Suweiyi Formation; ③ The formation pressure coefficient of the Paleogene Kumugeliemu Group composite salt rock section is the highest at 2.2; ④ The formation pressure coefficient of the mudstone section at the bottom of the Paleogene Kumugeliemu Group to the Cretaceous System decreases to about 1.70. Based on the analysis of the four pressure systems, considering the sealing of the undiagenetic loose formations on the surface, a five-layer casing structure was designed for this example well to ensure the safety, smoothness and integrity of the well. In addition, considering that the pressure coefficient of the target layer of the well is 1.70, the well depth is 7000 meters, the absolute value of the formation pressure is predicted to be 119MPa, and it is a gas well, the pressure level of the wellhead equipment, blowout preventer and other well control equipment is designed to be 140MPa to ensure well control safety.

[0089] According to the above technical solution, the drilling speed increase of this embodiment will directly produce the following two benefits: (1) The drilling speed-up method of this embodiment predicts the geomechanical parameters of ultra-deep oil and gas fields. By focusing on predicting the geomechanical parameters of oil and gas fields such as the direction and size distribution of geostress, the distribution of rock mechanics parameters, and the characteristics of natural fractures and fracture mechanics, and analyzing the influence of the above geomechanical parameters of oil and gas fields on the quality of fractured reservoirs, the understanding of stress controlling reservoirs and production is proposed, and the distribution of reservoir quality is clarified. Based on this, the well points are selected and the well trajectories are optimized, which can lay a foundation for high well production from the geological source; (2) The drilling speed-up method of this embodiment is based on the above-mentioned geomechanical parameter prediction results, carries out pore pressure prediction of the entire formation, clarifies the vertical distribution characteristics of pore pressure, and then analyzes the wellbore stability of formations such as conglomerate, mudstone, and composite salt rock, thereby optimizing the drilling fluid density, wellbore structure, and pressure level design of well control equipment in the entire well section, providing guarantees for well control safety and drilling speed-up.

[0090] Embodiment 3 A third embodiment of the present invention provides a method for increasing production, the method comprising the following steps: Step S301: Drilling is performed using the well location and well trajectory determined by the well location and well trajectory determination method described above.

[0091] Step S302: After drilling is completed, a fracturability profile is obtained according to the formation fracturability model, the wellbore is divided into vertical reservoirs for completion quality evaluation, and the reservoir is transformed according to the evaluation results.

[0092] The wellbore vertical reservoir completion quality evaluation results obtained through the above steps can be used to optimize the reservoir transformation method, oil testing layer section, perforation layer section, construction scale, construction pressure and pumping program.

[0093] Further, in a possible implementation, in step S302, the process of obtaining the fracturability profile according to the formation fracturability model and dividing the wellbore vertical reservoir completion quality evaluation may include but is not limited to the following sub-steps S3021 to S3023 (such as Figure 8 as shown).

[0094] Sub-step S3021: Establish a formation fracturability model based on rock brittleness, toughness, ground stress and shear slip pressure of natural fractures.

[0095] Sub-step S3022: obtaining a fracturability profile according to a formation fracturability model; Sub-step S3023: Based on the fracturability profile, the wellbore is divided into vertical reservoirs for completion quality evaluation.

[0096] Further, in a possible implementation manner, the pressure of shear slip of the natural fracture in sub-step S3021 can be obtained in the following manner: (1) Evaluate rock mechanical parameters based on well logging data, establish a one-dimensional geomechanical model, and obtain the current geostress profile; (2) Based on the natural fracture information of the wellbore obtained from the imaging logging data and the current ground stress profile, the stress on the natural fractures of the wellbore is analyzed to obtain the pressure at which the natural fractures undergo shear slip.

[0097] According to the above technical solution, the transformation and increase in production of this embodiment will directly produce the following benefits: The transformation and production increase method of this embodiment is based on three-dimensional pressure prediction and geostress field modeling, and analyzes the stress characteristics of the three-dimensional natural fractures predicted by geology. Then, a fracturing algorithm is established by comprehensively considering four factors, namely stress, cracks, brittleness and fracture toughness, to form a prediction of the vertical and horizontal distribution characteristics of fracturing. Combined with the vertical and horizontal mechanical characteristic distribution of natural fractures, a completion quality evaluation system for ultra-deep fractured reservoirs is formed. Based on this, the transformation method, transformation layer section, perforation section, segmentation and classification scheme, construction pressure and other parameters during completion fracturing transformation are optimized to support transformation and substantial production increase.

[0098] Embodiment 4 The fourth embodiment of the present invention takes the Keshen 10 structure as an example and applies the transformation and production increase method of the above embodiment to this area.

[0099] The Keshen 10 structure is controlled by the Keshen 6 fault and the Kelasu fault. The Keshen 6 fault is the southern boundary fault, with the Keshen 10 and Keshen 6 structures on the upper plate and the Keshen 2 structure on the lower plate. The Kelasu fault is the northern boundary fault of the Keshen 10 structure, with the Kela 8 structure on the upper plate and the 10 structure on the lower plate.

[0100] Fig. 9 The distribution profile of the three-dimensional geostress field obtained by conducting a three-dimensional heterogeneous stress field study on Keshen 10 is shown. It can be seen that the current geostress state of Keshen 10 is: the maximum horizontal principal stress orientation is NW in the west, the central anticline high position is nearly NS, and gradually changes to NE to the east. The stress orientation changes from nearly NS to NE from north to south. The overall distribution law of the current minimum horizontal principal stress value and horizontal stress difference is similar to the contour line and is ring-shaped. It is low in the high part of the anticline and gradually increases toward the wing. The current minimum horizontal principal stress value of the Bashijiqik Formation in the Keshen 10 gas reservoir is distributed between 110 and 160 MPa, and the horizontal stress difference is about 35 to 50 MPa.

[0101] Regarding the optimization of well locations and well trajectories, the low stress zone of the Keshen 10 gas reservoir is located to the north of the projection lines of the Kela 1 and Kela 8 faults, that is, in the superposition area of ​​the upper plate structure. Taking into account geological factors and reservoir geomechanical characteristics, this low stress zone is a sweet spot for well location deployment. If a vertical well is used, faults such as Kela 1 and Kela 8 and thicker salt layers will be encountered, which may bring a series of complex engineering problems and safety risks to drilling. Based on this, it is necessary to consider the current ground stress state for well location deployment and optimization of high-angle wellbore trajectories.

[0102] Fig.10 The analysis results of the wellbore stability of simulated vertical wells and highly deviated wells are shown. It can be seen that the vertical well has only a very narrow safe mud window in the Kumugeliemu Group (salt layer) (if the mud density is too low, the wellbore collapse is likely to occur, and if the mud density is too high, mud loss will occur), and the wellbore stability is poor, which is not conducive to safe and rapid drilling. If it is designed as a highly deviated well, the wellhead is biased to the south and the inclination is built to the north, not only can shallow faults be avoided, but the thickness of the salt layer encountered is also thin, and the mud window of the salt layer is wider (greater than 0.3MPa / 100m), and the wellbore stability is better, which has a positive effect on safe, stable and rapid drilling. Therefore, it can be considered that the scheme of using highly deviated wells in Keshen 1002 well is better than the scheme of vertical wells.

[0103] Practice has shown that the Keshen 1002 well has achieved high-yield oil and gas flow, proving that the optimization of high-angle wellbore trajectory considering the current ground stress state is correct, reasonable and effective.

[0104] In terms of optimization of transformation and production increase, through imaging logging data, a total of 87 fractures were interpreted in the Bashijiqik Formation of Keshen 10 Well, with an average fracture density of 0.3 fractures / m, and the fracture density of the second section of Bashijiqi Formation was about 0.8 fractures / m. Fig.11 As shown in Figure 2, the natural fractures are concentrated in the NWW direction and present a small angle (about 15° on average) with the maximum horizontal principal stress. Fig.12 As shown in the figure, the natural fractures are mostly inclined at angles greater than 60°, and are mainly high-angle fractures. Based on the current in-situ stress evaluation results of the well, the opening of natural fractures was simulated by combining the angle between the natural fracture direction and the maximum principal stress orientation (force-fracture angle). The results show that: Fig.13 (a) shows that when the bottom hole net pressure is 1.96MPa / 100m, a natural fracture is opened with an opening rate of 1.1%. Fig.13 (b) shows that when the bottom hole net pressure is 2.05 MPa / 100m, the opening rate is about 69%; Fig.13 (c) in the figure shows that when the net bottom hole pressure is 2.18MPa / 100m, the natural fractures are almost completely opened.

[0105] Generally speaking, 2.05 MPa / 100m is the upper limit of pressure that can be achieved in engineering. Therefore, it is believed that the natural fractures in Keshen 10 Well have a high opening rate (about 70%) during the fracturing process, which is conducive to the communication and migration of oil and gas. Small-scale acidizing and acid fracturing can be used to unblock and dredge natural fractures; if the force-fracture angle is large (45°~60°) and the natural fracture opening rate is low (less than 50%), it is necessary to consider using fracture network acid fracturing and fracture network fracturing to activate natural fractures and artificially create complex fracture networks; if natural fractures are not well developed and the force-fracture angle is large or nearly vertical, it is necessary to use sand fracturing to artificially create main fractures. Therefore, it is preferred to perforate layers with developed natural fractures (fracture density greater than 0.3 / m), relatively low horizontal stress (lower than the average value of 2~3MPa), small force-fracture angle (<45°), and low fracture opening pressure (<2.05 MPa / 100m). Nowadays, geostress analysis is an important evaluation link before reservoir transformation, which helps to increase oil and gas production and efficiency.

[0106] During the drilling process of Keshen 1002 Well, the staff further optimized 8 measures including wellbore trajectory, drilling parameters and wellbore cleaning. In view of the development characteristics of the thick salt layer in Keshen 10X Well, the vertical section of the well adopted the Power-V + PDC combination drilling speed-up technology with oil-based drilling fluid, and the practical and effective cycle was 21 days earlier than the design. The rotary steerable drilling speed-up tool was selected for the deflection section, achieving the dual purpose of deflection and speed-up, 18 days earlier than the design cycle. After the completion and transformation, the production increase effect was obvious, with a daily gas production of 740,000 cubic meters, and the unobstructed flow rate increased from 300,000 cubic meters in the adjacent vertical well to 2.5 million cubic meters, an increase of 8 times.

[0107] In summary, the improved production-increasing method of the present invention establishes a comprehensive evaluation system for high-precision geomechanical parameter fields of oil and gas fields, and uses the comprehensive evaluation results of geomechanical parameters of oil and gas fields to optimize well positions and well trajectories, ensuring the preconditions for improving drilling speed and production; during drilling, the drilling parameters are optimized through the comprehensive evaluation results of geomechanical parameters of oil and gas fields to achieve the goal of increasing drilling speed; after completion, the completion and stimulation parameters are optimized through the comprehensive evaluation results of geomechanical parameters of oil and gas fields to achieve a significant increase in production after stimulation, thereby achieving the ultimate goal of efficient development of complex oil and gas reservoirs.

[0108] In the implementation process of the above-mentioned improved production-increasing method, the following specific problems can be solved: ① Combining geological structure modeling, well-seismic joint geophysical technology with deep-earth rock mechanics research to innovatively form a comprehensive evaluation technology method for geomechanical parameter fields of oil and gas fields; ② Solving the technical problems that the existing medium- and shallow-layer rock mechanics theories and constitutive relations are not applicable to ultra-deep layers and the evaluation accuracy of ultra-deep layer rock mechanics parameters is low; ③ Solving the quantitative prediction problem of the influence of in-situ stress fields, rock strength, pore pressure, etc. on the development of natural fractures and the permeability around fractures in reservoir quality evaluation; ④ Solving the technical problem of predicting the activity of natural fractures and fracture mechanics under a strong stress background; ④ Solving the technical problem of predicting the stability of the drilling wellbore under the conditions of special lithological bodies and the development of fractures (faults); ⑤ Solving the technical problem of geomechanical evaluation for ultra-deep oil and gas reservoir stimulation.

[0109] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0110] In addition, it should be noted that, in the case of no contradiction, the various specific technical features described in the above specific embodiments can be combined in any suitable manner. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods.

[0111] Furthermore, any combination can be made between different embodiments of the present invention as long as it does not violate the idea of the present invention, and it should also be regarded as the content disclosed by the present invention.

Claims

1. A method for determining well location and well trajectory, It is characterized in that The method comprises: According to the formation pressure test and the flow phase constraints of each formation, a three-dimensional rock mechanics parameter field model of the entire formation is established to obtain the rock mechanics parameters of the entire formation; According to the geological structure and the formation pressure field of each layer, a three-dimensional stress field prediction model for the entire layer system is established to obtain the three-dimensional stress field parameters of the entire layer system; A natural fracture activity prediction model is established based on the rock mechanics parameters of the entire layer, the three-dimensional stress field parameters of the entire layer, and the three-dimensional natural fracture model to evaluate fracture activity. Determine the well location based on the 3D current geostress model, 3D fracturability prediction model and fracture activity; The well trajectory is determined based on fracture activity, a three-dimensional fracturability prediction model, a three-dimensional current geostress model, and a three-dimensional collapse pressure prediction model.

2. The method for determining the well location and trajectory according to claim 1, It is characterized in that According to the formation pressure test and the flow phase constraints of each formation, a three-dimensional rock mechanics parameter field model of the entire formation is established to obtain the rock mechanics parameters of the entire formation, including: Based on the structural interpretation and geological stratification comparison data, a three-dimensional structural framework model of the entire layer from the ground to the target layer is established; Based on the 3D structural framework model of the entire stratum, logging data and logging interpretation results, the sedimentary facies / lithological facies model of each stratum in the target area is established; Using sedimentary facies model or lithofacies model as constraints, establish a rock physical parameter field model for the entire stratum system; A three-dimensional rock mechanics parameter field model of the entire formation is established based on the rock physical parameter field model of the entire formation, formation pressure testing and flow phase constraints of each formation from the ground.

3. The method for determining well location and well trajectory according to claim 2, It is characterized in that The full-stratum rock physical parameter field model includes: sedimentary phase / lithological phase parameter model, porosity parameter model and density parameter model; The full-layer rock mechanics parameter model includes: Young's modulus, Poisson's ratio and compressive strength.

4. The method for determining well location and well trajectory according to claim 2, It is characterized in that The method of establishing a three-dimensional rock mechanics parameter field model of the entire formation system according to the formation pressure test and the flow phase constraints of each formation to obtain the rock mechanics parameters of the entire formation system also includes: Before establishing the full-stratum rock physical parameter field model with the sedimentary facies or lithofacies model as a constraint, the sedimentary facies model or lithofacies model is selected based on the rock mechanics experimental results and the one-dimensional rock mechanics parameter interpretation results.

5. The method for determining well location and well trajectory according to claim 1, It is characterized in that The method of establishing a three-dimensional full-layer stress field prediction model based on the geological structure and the formation pressure field of each layer to obtain the three-dimensional stress field parameters of the full-layer system includes: Establish the formation pressure field of each formation; Boundary conditions are set according to the strength of the tectonic stress background in the target area, and the finite element numerical simulation method is used to establish the three-dimensional stress field parameters of the entire layer system.

6. The method for determining well location and well trajectory according to claim 5, It is characterized in that The method of establishing a three-dimensional full-layer stress field prediction model according to the geological structure and the formation pressure field of each layer to obtain the three-dimensional stress field parameters of the full-layer system also includes: The formation pressure of each layer is evaluated, and the evaluation results are compared with the three-dimensional stress field parameters of the entire layer system. If the accuracy requirements are not met, the boundary conditions are reset and the finite element numerical simulation calculation is performed again.

7. The method for determining well location and well trajectory according to claim 1, It is characterized in that The three-dimensional stress field parameters of the whole layer system include: vertical stress, maximum horizontal principal stress, minimum horizontal principal stress, and principal stress direction; The method of establishing a natural fracture activity prediction model based on the rock mechanics parameters of the entire layer system, the three-dimensional stress field parameters of the entire layer system and the three-dimensional natural fracture model to evaluate fracture activity includes: Collecting the three-dimensional stress field parameters of each of the full-layer systems to each crack of the three-dimensional natural fracture model; Calculate the effective normal stress σ of each crack Ne and shear stress τ, according to the shear stress τ and the effective normal stress σ Ne The ratio of is used to evaluate the fracture activity.

8. The method for determining well location and well trajectory according to claim 7, It is characterized in that The effective normal stress σ Ne Obtained by the following formula: (Formula 1) The shear stress τ is obtained by the following formula: (Formula 2) Among them, l = cos(θ), m = sin(θ)sin(φ-γ), n = sin(θ)cos(φ-γ); θ is the crack inclination; φ is the crack dip; γ is the angle between the maximum horizontal principal stress and the north direction; σ 1 is the stress with the largest stress value among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 2 is the stress in the middle of the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress, σ 3 It is the smallest stress among the vertical stress, the maximum horizontal principal stress, and the minimum horizontal principal stress.

9. The method for determining well location and well trajectory according to claim 1 or 7, It is characterized in that The three-dimensional natural fracture prediction model is obtained by the following method: According to the distribution trend of fractures, a three-dimensional natural fracture DFN model of the target area is established; The three-dimensional natural fracture DFN model is corrected by the single well fracture interpretation results to form the three-dimensional natural fracture prediction model.

10. The method for determining well location and well trajectory according to claim 9, It is characterized in that The three-dimensional natural fracture DFN model of the target area is established according to the distribution trend of the fractures, including: According to the fracture interpretation results, geological and structural regional background laws and core fracture description results, the fracture types of single wells are obtained, fault-derived fractures and fractures related to fold deformation are divided, and the occurrence parameters of various fractures are analyzed; The distribution trends of fault-related cracks and fold-related cracks are predicted respectively.

11. The method for determining well location and well trajectory according to claim 10, It is characterized in that The prediction of the distribution trends of fault-related cracks and fold-related cracks respectively includes: For fault-related cracks: obtain the distribution range of fault-derived cracks through three-dimensional fault recovery calculation, and obtain the distribution trend of all fault-derived cracks in the study area through calculation of fault distance size; For fold-related cracks: through fold recovery calculation, the magnitude of structural deformation is obtained in order to analyze the distribution of cracks caused by structural deformation; through the calculation of fold deformation, the distribution trend of cracks generated in all strata in the study area during the fold deformation process is obtained.

12. The method for determining well location and well trajectory according to claim 1, It is characterized in that The method of determining the well location based on the three-dimensional current geostress model, the three-dimensional fracturability prediction model and the fracture activity includes: Based on the three-dimensional current geostress model, the three-dimensional fracturability prediction model, and the natural fracture activity prediction model, the well location is preferably determined in the target layer with weak stress and the area with good fracture activity and high fracturability of the target layer.

13. The method for determining well location and well trajectory according to claim 1, It is characterized in that The method of determining the well trajectory according to the fracture activity, the three-dimensional fracturability prediction model, the three-dimensional current ground stress model and the three-dimensional collapse pressure prediction model includes: According to the three-dimensional current geostress model, the three-dimensional fracturability prediction model, the natural fracture activity prediction model and the three-dimensional collapse pressure prediction model, the well trajectory that encounters the most natural fractures, has high formation fracturability and high formation collapse pressure is preferably drilled.

14. The method for determining well location and well trajectory according to claim 12 or 13, It is characterized in that The three-dimensional current geostress model is obtained by: Evaluate the rock mechanical parameters according to the logging data, establish a one-dimensional geomechanical model, and evaluate the formation pore pressure; Perform well-seismic joint inversion to obtain the three-dimensional wave impedance attribute volume of the entire formation; According to the relationship between P-wave and S-wave and density established by drilling, the wave impedance body is converted into P-wave, density, S-wave and formation mud content data; Predict formation pressure based on P-wave, density, S-wave and formation mud content to obtain formation pressure prediction data; The three-dimensional current geostress model including the pressure distribution in three-dimensional space is formed according to the predicted data of formation pressure and the wellbore stability of different lithology formations in the whole wellbore.

15. The method for determining well location and well trajectory according to claim 14, It is characterized in that The formation pressure includes formation pore pressure, formation collapse pressure, formation fracture pressure, leakage pressure and closure pressure; Predicting the formation pore pressure by using a nonlinear trend line method for sandstone and mudstone and / or a multi-rock physical fitting method for carbonate rocks; The Mohr-Coulomb theory is used to predict the formation collapse pressure and the formation fracture pressure.

16. The method for determining well location and well trajectory according to claim 14, It is characterized in that The three-dimensional present-day geostress model is corrected using the coring data and the measured data to obtain a corrected three-dimensional present-day geostress model.

17. The method for determining well location and well trajectory according to claim 12 or 13, It is characterized in that The three-dimensional fracturability prediction model is obtained by: According to the logging data and the rock mechanical parameters of the target layer, a one-dimensional geomechanical model is established to obtain the current geostress profile; Based on the natural fracture information of the wellbore and the current ground stress profile obtained from the imaging logging data, the pressure at which shear slip occurs in the natural fracture is obtained; Establish a formation fracturability model based on rock brittleness, toughness, ground stress and shear slip pressure of natural fractures; A three-dimensional fracturing prediction model is established based on the formation fracturing model.

18. A method for increasing drilling speed. It is characterized in that Drilling is performed using the well location and well trajectory determined by the well location and well trajectory determination method described in any one of claims 1 to 17.

19. A method for increasing production through transformation, It is characterized in that The method comprises: Drilling by using the well location and well trajectory determined by the well location and well trajectory determination method according to any one of claims 1 to 17; After drilling is completed, the fracturability profile is obtained according to the formation fracturability model, the wellbore vertical reservoir is divided for completion quality evaluation, and the reservoir is transformed according to the evaluation results.

20. The method for increasing production according to claim 19, It is characterized in that The method of obtaining a fracturability profile according to the formation fracturability model and dividing the wellbore vertical reservoir completion quality evaluation includes: Establish a formation fracturability model based on rock brittleness, toughness, ground stress and shear slip pressure of natural fractures; Obtaining a fracturability profile according to a formation fracturability model; According to the fracturability profile, the wellbore vertical reservoir is divided for completion quality evaluation.

21. The method for increasing production according to claim 20, It is characterized in that The pressure at which the natural fracture undergoes shear slip is obtained by: The rock mechanical parameters were evaluated based on the logging data, a one-dimensional geomechanical model was established, and the current geostress profile was obtained; Based on the natural fracture information of the wellbore obtained from the imaging logging data and the current ground stress profile, the stress on the natural fractures of the wellbore is analyzed to obtain the pressure at which the natural fractures undergo shear slip.

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