Real-time prediction method, device, equipment and storage medium for geostress

Abstract

The present application provides a method, device, equipment and storage medium for real-time prediction of geostress. The method obtains geostress parameters of a to-be-predicted area, wherein the geostress parameters include a first geostress parameter and a second geostress parameter, wherein the first geostress parameter is a structural strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a structural strain coefficient along a horizontal minimum principal stress direction; determines a correction parameter, wherein the correction parameter is calculated by construction parameters obtained during fracturing construction; corrects the geostress parameter according to the correction parameter to obtain a corrected geostress parameter; determines the dynamic geostress of the to-be-predicted area according to the corrected geostress parameter; and determines a fracturing construction plan for the to-be-predicted area according to the dynamic geostress, thereby enabling accurate and effective oil exploration.

Description

Technical Field

[0001] The present invention relates to the technical field of petroleum exploration, and in particular to a method, device, equipment and storage medium for real-time prediction of ground stress. Background Art

[0002] Geostress is an important parameter in the geomechanical model of oil and gas reservoirs. In the exploration and development of low-permeability oil and gas fields, reservoirs often need to undergo a certain scale of fracturing transformation to obtain industrial production capacity. The geostress field plays an important role in controlling the formation fracture pressure, the formation and distribution of cracks during fracturing transformation, etc. The direction of geostress controls the fracture azimuth and orientation of artificial fractures during fracturing, as well as their relationship with natural fractures. The magnitude of geostress controls the scale of artificial fractures and the effective transformation volume. Therefore, accurately predicting the geostress field of underground strata is of great significance for optimizing reservoir transformation plans in the exploration and development of oil and gas fields.

[0003] In related technologies, linear elastic theory is usually used to predict geostress based on well logging data. The main models used are the following: Mohr-Columb model, uniaxial strain model, Huang Rongzun model of Petroleum University and combined spring model. Well logging data are directly input into the above models to predict geostress.

[0004] However, in the prior art, the accuracy of geostress prediction is low, and it is difficult to determine an accurate and effective fracturing construction plan based on the predicted geostress, thereby conducting accurate and effective oil exploration. Summary of the invention

[0005] The present application provides a method, device, equipment and storage medium for real-time prediction of geostress, thereby solving the technical problem in the prior art that the accuracy of geostress prediction is low and it is difficult to accurately and effectively determine a fracturing construction plan based on the predicted geostress, thereby accurately and effectively conducting oil exploration.

[0006] In a first aspect, the present application provides a method for real-time prediction of geostress, comprising:

[0007] Acquire geostress parameters of the area to be predicted, wherein the geostress parameters include a first geostress parameter and a second geostress parameter, wherein the first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction;

[0008] Determining correction parameters, wherein the correction parameters are calculated by using construction parameters obtained during fracturing construction;

[0009] Correcting the geostress parameter according to the correction parameter to obtain a corrected geostress parameter;

[0010] Determining the dynamic geostress of the area to be predicted according to the corrected geostress parameter;

[0011] A fracturing construction plan for the area to be predicted is determined according to the dynamic geostress.

[0012] Here, the embodiment of the present application first obtains the geostress parameters, wherein the above-mentioned geostress parameters include the tectonic strain coefficient along the direction of the maximum horizontal principal stress and the tectonic strain coefficient along the direction of the minimum horizontal principal stress, and then determines the correction parameters according to the construction parameters obtained during the fracturing construction, and corrects the geostress parameters by the correction parameters. Since the correction parameters are calculated by the construction parameters obtained during the fracturing construction, the determination of the horizontal maximum principal stress in the embodiment of the present application is combined with the changes in the rock fracturing process in the area to be predicted, and the dynamic geostress is determined by the real fracturing data parameters. The fixed geostress predicted before fracturing is corrected according to the dynamic geostress during the fracturing process, so that the predicted dynamic geostress is less different from the real geostress reflected in the actual fracturing process, thereby improving the accuracy of geostress prediction and enabling accurate and effective oil exploration.

[0013] Optionally, the construction parameters include formation fracture pressure, formation pore pressure and rock mechanics parameters;

[0014] Determining the correction parameter comprises:

[0015] determining a first vertical stress according to the geostress parameter;

[0016] The correction parameter is obtained by calculation according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress.

[0017] Here, the construction parameters for determining the correction parameters in the embodiment of the present application include formation fracture pressure, formation pore pressure and rock mechanics parameters, and utilize the real fracturing data parameters of the formation during the fracturing process. The real geostress of the formation can be determined based on the real formation fracture pressure that changes during the fracturing process, and the fixed geostress predicted before fracturing can be dynamically corrected. The correction parameters are determined by these parameters and the first vertical stress determined based on the geostress parameters, thereby obtaining accurate and dynamic correction parameters, which facilitates real-time and accurate correction of the geostress parameters, thereby further improving the accuracy of geostress determination.

[0018] Optionally, before obtaining the correction parameter by calculating according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress, the method further includes:

[0019] Performing fracturing construction on the area to be predicted to obtain formation fracture pressure;

[0020] Conducting actual measurements on other wells in the oil and gas reservoirs in the area to be predicted to obtain formation pore pressure;

[0021] A rock mechanics experiment is performed on the area to be predicted to obtain rock mechanics parameters, wherein the rock mechanics parameters include formation porosity, rock contact porosity and rock tensile strength.

[0022] Here, the embodiment of the present application obtains the formation breakdown pressure from the fracturing data, obtains the formation pore pressure based on actual measurements of other wells in the oil and gas reservoir, and obtains rock mechanics parameters including formation porosity, rock contact porosity and rock tensile strength based on rock mechanics experiments. The real fracturing data parameters of the formation during the fracturing process are utilized. The real formation stress can be determined according to the real formation breakdown pressure that changes during the fracturing process, and the fixed ground stress predicted before fracturing can be dynamically corrected. According to the measurement and acquisition of the above experiments, real-time and accurate dynamic parameters are obtained, thereby improving the accuracy of determining the correction parameters and further improving the accuracy of determining the ground stress.

[0023] Optionally, the correcting the geostress parameter according to the correction parameter to obtain the corrected geostress parameter includes:

[0024] Determining a first horizontal minimum principal stress according to the geostress parameter;

[0025] The first horizontal minimum principal stress is made equal to the correction parameter, and the first geostress parameter is made a first multiple of the second geostress parameter, to obtain a corrected first geostress parameter and a corrected second geostress parameter, wherein the first multiple is greater than 1 and less than 10.

[0026] Here, an embodiment of the present application provides a method for correcting geostress parameters according to correction parameters, wherein a first-level minimum principal stress is determined by the geostress parameters, and the geostress parameters are corrected by the correction parameters so that the corrected data satisfies that the first-level minimum principal stress is equal to the correction parameter and the first geostress parameter is the first multiple of the second geostress parameter, thereby realizing dynamic correction of the geostress parameters, improving the accuracy of geostress prediction, and enabling accurate and effective oil exploration.

[0027] Optionally, determining the dynamic geostress of the area to be predicted according to the corrected geostress parameter includes:

[0028] The maximum horizontal principal stress is determined according to the static Poisson's ratio, the formation Biot coefficient, the rock elastic modulus, the corrected in-situ stress parameter, and the formation pore pressure.

[0029] The embodiment of the present application combines the geostress parameters corrected by dynamic correction parameters with the static Poisson's ratio, formation Biot coefficient, rock elastic modulus and formation pore pressure to determine the horizontal maximum principal stress, combines static and dynamic prediction data, further improves the accuracy of geostress prediction, and enables accurate and effective oil exploration.

[0030] Optionally, determining the fracturing construction scheme of the area to be predicted according to the dynamic geostress includes:

[0031] Determine a fracturing construction design scheme for the area to be predicted according to the horizontal maximum principal stress;

[0032] The fracturing construction is performed on the area to be predicted according to the fracturing construction design plan.

[0033] Here, the embodiment of the present application determines the fracturing construction design scheme for the area to be predicted based on the horizontal maximum principal stress. Since the determination of the horizontal maximum principal stress in the embodiment of the present application is combined with the changes in the rock fracturing process in the area to be predicted, the dynamic geostress is determined by the real fracturing data parameters, and the fixed geostress predicted before fracturing is corrected according to the dynamic geostress during the fracturing process, so that the predicted dynamic geostress is less different from the real geostress reflected in the actual fracturing process. Therefore, the fracturing construction design scheme is more suitable for the area to be predicted and can carry out more accurate oil exploration.

[0034] In a second aspect, an embodiment of the present application provides a device for real-time prediction of ground stress, comprising:

[0035] An acquisition module, used to acquire geostress parameters of the area to be predicted, wherein the geostress parameters include a first geostress parameter and a second geostress parameter, wherein the first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction;

[0036] A first determination module is used to determine correction parameters, where the correction parameters are calculated using construction parameters obtained during fracturing construction;

[0037] A correction module, used for correcting the geostress parameter according to the correction parameter to obtain a corrected geostress parameter;

[0038] A second determination module is used to determine the dynamic geostress of the area to be predicted according to the corrected geostress parameter;

[0039] A processing module is used to determine a fracturing construction plan for the area to be predicted according to the dynamic ground stress.

[0040] Optionally, the construction parameters include formation fracture pressure, formation pore pressure and rock mechanics parameters;

[0041] The first determination module is specifically used to determine the first vertical stress according to the ground stress parameter;

[0042] The correction parameter is obtained by calculation according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress.

[0043] Optionally, before the first determination module calculates and obtains the correction parameter according to the formation fracture pressure, the formation pore pressure, the rock mechanical parameters and the first vertical stress, the apparatus further includes:

[0044] A construction module, used for performing fracturing construction on the area to be predicted to obtain the formation fracture pressure;

[0045] A measurement module is used to measure other wells in the oil and gas reservoirs in the area to be predicted to obtain the formation pore pressure;

[0046] The experimental module is used to perform rock mechanics experiments on the area to be predicted to obtain rock mechanics parameters, wherein the rock mechanics parameters include formation porosity, rock contact porosity and rock tensile strength.

[0047] Optionally, the correction module is specifically used for:

[0048] Determining a first horizontal minimum principal stress according to the geostress parameter;

[0049] The first horizontal minimum principal stress is made equal to the correction parameter, and the first geostress parameter is made a first multiple of the second geostress parameter, to obtain a corrected first geostress parameter and a corrected second geostress parameter, wherein the first multiple is greater than 1 and less than 10.

[0050] Optionally, the second determining module is specifically configured to:

[0051] The maximum horizontal principal stress is determined according to the static Poisson's ratio, the formation Biot coefficient, the rock elastic modulus, the corrected in-situ stress parameter, and the formation pore pressure.

[0052] Optionally, the processing module is specifically used to determine the fracturing construction design scheme of the area to be predicted according to the horizontal maximum principal stress;

[0053] The fracturing construction is performed on the area to be predicted according to the fracturing construction design plan.

[0054] In a third aspect, an embodiment of the present application provides a real-time prediction device for ground stress, comprising: at least one processor and a memory;

[0055] The memory stores computer-executable instructions;

[0056] The at least one processor executes the computer-executable instructions stored in the memory, so that the at least one processor executes the real-time prediction method for geostress as described in the first aspect and various possible designs of the first aspect.

[0057] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, in which computer execution instructions are stored. When a processor executes the computer execution instructions, the real-time prediction method of geostress as described in the first aspect and various possible designs of the first aspect is implemented.

[0058] In a fifth aspect, an embodiment of the present invention provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the real-time prediction method of ground stress as described in the first aspect and various possible designs of the first aspect.

[0059] The embodiments of the present application provide a method, device, equipment and storage medium for real-time prediction of geostress, wherein the method first obtains geostress parameters, wherein the geostress parameters include a tectonic strain coefficient along the direction of the maximum horizontal principal stress and a tectonic strain coefficient along the direction of the minimum horizontal principal stress, and then determines correction parameters based on the construction parameters obtained during the fracturing construction, and corrects the geostress parameters through the correction parameters. Since the correction parameters are calculated based on the construction parameters obtained during the fracturing construction, the determination of the maximum horizontal principal stress in the embodiments of the present application is combined with the changes in the rock fracturing process in the area to be predicted, and the dynamic geostress is determined through the real fracturing data parameters. The fixed geostress predicted before fracturing is corrected based on the dynamic geostress during the fracturing process, so that the predicted dynamic geostress is less different from the real geostress reflected in the actual fracturing process, thereby improving the accuracy of geostress prediction, providing a more scientific guiding basis for timely adjustment of the next fracturing construction plan, and enabling accurate and effective oil exploration. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0061] Figure 1 A schematic diagram of a real-time prediction system architecture for ground stress provided in an embodiment of the present application;

[0062] Figure 2 A schematic diagram of a real-time prediction system architecture for ground stress provided in an embodiment of the present application;

[0063] Figure 3 A schematic diagram of another method for real-time prediction of geostress provided in an embodiment of the present application;

[0064] Figure 4 A schematic diagram of the structure of a real-time prediction device for ground stress provided in an embodiment of the present application;

[0065] Figure 5 A schematic diagram of the structure of a real-time prediction device for geostress provided in an embodiment of the present application. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0067] The terms "first", "second", "third", and "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or devices.

[0068] Geostress is an important parameter in the geomechanical model of oil and gas reservoirs. In the exploration and development of low-permeability oil and gas fields, reservoirs often need to undergo a certain scale of fracturing to achieve industrial production capacity. The geostress field plays an important role in controlling the formation fracture pressure, the formation and distribution of cracks during fracturing, etc. The direction of geostress controls the fracture azimuth and orientation of artificial fractures during fracturing, as well as their relationship with natural fractures. The magnitude of geostress controls the scale of artificial fractures and the effective transformation volume. Therefore, accurately predicting the geostress field of underground strata is of great significance for optimizing reservoir transformation plans in the exploration and development of oil and gas fields.

[0069] In related technologies, linear elastic theory is usually used to predict geostress based on well logging data. The main models used are the following: Mohr-Columb model, uniaxial strain model, Huang Rongzun model of Petroleum University and combined spring model. Well logging data are directly input into the above models to predict geostress.

[0070] However, the geostress predicted by the prior art using the linear elastic theory is static and can only be predicted based on fixed logging data before fracturing, but cannot be predicted based on the changing fracturing data during the fracturing process. This results in a large difference between the predicted geostress and the actual geostress reflected during the actual fracturing process. That is, the prior art has a technical problem of low accuracy in geostress prediction, making it difficult to conduct accurate and effective oil exploration based on the predicted geostress.

[0071] In order to solve the above problems, the embodiments of the present application provide a method, device, equipment and computer-readable storage medium for real-time prediction of geostress. By extracting key information from the query information input by the user, and based on the key information such as entities, attributes or relationships contained in the query information, the triple data corresponding to the query information can be determined in a preset database, and a knowledge graph is established based on the triple data, and the knowledge graph is displayed to the user. By centrally storing all data in a unified format in the preset database, the time spent by well loggers in real-time prediction of geostress is reduced, and the efficiency of real-time prediction of geostress by well loggers is improved.

[0072] Optional, Figure 1 A schematic diagram of the architecture of a real-time prediction system for ground stress provided in an embodiment of the present application. Figure 1 In the above architecture, the above architecture includes at least one of a receiving device 101, a processor 102 and a display device 103.

[0073] It is understandable that the structure illustrated in the embodiment of the present application does not constitute a specific limitation on the architecture of the real-time prediction system for ground stress. In other feasible implementations of the present application, the above architecture may include more or fewer components than those shown in the figure, or combine certain components, or split certain components, or arrange the components differently, which can be determined according to the actual application scenario and is not limited here. Figure 1 The components shown may be implemented in hardware, software, or a combination of software and hardware.

[0074] In a specific implementation process, the receiving device 101 may be an input / output interface or a communication interface.

[0075] The processor 102 may first obtain geostress parameters, wherein the geostress parameters include a tectonic strain coefficient along the direction of the maximum horizontal principal stress and a tectonic strain coefficient along the direction of the minimum horizontal principal stress, and then determine correction parameters according to the construction parameters obtained during the fracturing construction, and correct the geostress parameters by means of the correction parameters. The dynamic geostress is determined by means of actual fracturing data parameters in combination with the changes in the rock fracturing process in the area to be predicted, and the fixed geostress predicted before fracturing is corrected according to the dynamic geostress during the fracturing process, so that the predicted dynamic geostress is less different from the actual geostress reflected in the actual fracturing process, thereby improving the accuracy of geostress prediction.

[0076] The display device 103 can be used to display the above results and the like.

[0077] The display device may also be a touch display screen, which is used to receive user instructions while displaying the above content to achieve interaction with the user.

[0078] It should be understood that the above-mentioned processor can be implemented by the processor reading instructions in the memory and executing the instructions, or it can be implemented by a chip circuit.

[0079] In addition, the network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field can know that with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0080] The technical solution of the present application is described in detail below in conjunction with specific embodiments:

[0081] Optional, Figure 2 A schematic diagram of a real-time prediction system architecture for geostress provided in an embodiment of the present application. The execution subject of the embodiment of the present application may be Figure 1 The specific execution subject of the processor 102 can be determined according to the actual application scenario. Figure 2 As shown, the method comprises the following steps:

[0082] S201: Obtaining geostress parameters of the area to be predicted.

[0083] The geostress parameters include a first geostress parameter and a second geostress parameter. The first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction.

[0084] Optionally, the first geostress parameter and the second geostress parameter may be obtained through rock mechanics experiments and experience in the area to be drilled.

[0085] The structural strain coefficient along the direction of the maximum horizontal principal stress is ε H The structural strain coefficient along the horizontal minimum principal stress direction is ε h express.

[0086] Optionally, the geostress parameters may also include the depth H0 of the logging start point, the density at the depth H0 of the unlogged section, the logging density at the depth H, the gravitational acceleration g, the static Poisson's ratio μ, the formation Biot coefficient α and the rock elastic modulus E, etc.

[0087] Optionally, the above-mentioned geostress parameters can be collected from drilling engineering data, or can be directly measured in the area to be drilled using a logging instrument, and the embodiments of the present application do not impose specific restrictions on this.

[0088] S202: Determine correction parameters.

[0089] The correction parameters are calculated through the construction parameters obtained during the fracturing operation.

[0090] Optionally, the correction parameter is a parameter calculated based on a parameter obtained during the fracturing construction process, that is, the correction parameter is calculated based on the formation fracture pressure obtained during the fracturing construction process.

[0091] Here, the correction parameter is the horizontal minimum principal stress determined during the hydraulic fracturing construction process. Since the dynamically changing horizontal minimum principal stress can be predicted based on the real fracturing data parameters that change during the fracturing process, that is, the real formation fracture pressure, the horizontal minimum principal stress here is the dynamic horizontal minimum principal stress.

[0092] Optionally, the construction parameters include formation fracture pressure, formation pore pressure and rock mechanics parameters; the correction parameters include:

[0093] The first vertical stress is determined according to the ground stress parameter; and the correction parameter is obtained according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress calculation.

[0094] Optionally, the formula for determining the correction parameter is as follows:

[0095]

[0096]

[0097] In the above formula, σ h is the correction parameter, P b is the formation fracture pressure, P p is the formation pore pressure, μ is the static Poisson’s ratio, is the formation porosity, is the rock contact porosity, σf is the tensile strength of rock, S v is the first vertical stress.

[0098] Among them, the unit of the above porosity can be expressed in percentage. If the unit of porosity is expressed in percentage, both the formation porosity and the rock contact porosity are expressed in percentage.

[0099] Here, the construction parameters for determining the correction parameters in the embodiment of the present application include formation fracture pressure, formation pore pressure and rock mechanics parameters. The correction parameters are determined by these parameters and the first vertical stress determined according to the ground stress parameters, thereby obtaining accurate and dynamic correction parameters, which facilitates real-time and accurate correction of the ground stress parameters, thereby further improving the accuracy of ground stress determination.

[0100] S203: Correcting the geostress parameter according to the correction parameter to obtain the corrected geostress parameter.

[0101] Optionally, the geostress parameters are corrected according to the correction parameters to obtain the corrected geostress parameters, including: determining the first horizontal minimum principal stress according to the geostress parameters; making the first horizontal minimum principal stress equal to the correction parameter, and making the first geostress parameter a first multiple of the second geostress parameter, to obtain the corrected first geostress parameter and the corrected second geostress parameter, wherein the first multiple is greater than 1 and less than 10.

[0102] Optionally, the first multiple here is represented by λ. Specifically, let the first horizontal minimum principal stress S h and the correction parameter, namely the dynamic horizontal minimum principal stress σ h The equation contains two unknowns, which are the structural strain coefficient ε along the direction of the horizontal maximum principal stress. H and the structural strain coefficient ε along the horizontal minimum principal stress direction h ; Then according to the first geostress parameter ε H The second geostress parameter ε is equal to λ times h , and substituting this relationship into the equation can give the corrected sum.

[0103] The first geostress parameter ε H The second geostress parameter ε is equal to λ times h The relationship is:

[0104] ε H =λε h , 1<λ<10

[0105] The specific value of λ in the above relationship is obtained through the ground stress test experiment of rock samples in the predicted area during the hydraulic fracturing construction process. The specific value of λ varies greatly in different regions, and λ is between 1-10.

[0106] Here, an embodiment of the present application provides a method for correcting geostress parameters according to correction parameters, wherein a first-level minimum principal stress is determined by the geostress parameters, and the geostress parameters are corrected by the correction parameters so that the corrected data satisfies that the first-level minimum principal stress is equal to the correction parameter and the first geostress parameter is the first multiple of the second geostress parameter, thereby realizing dynamic correction of the geostress parameters, improving the accuracy of geostress prediction, and enabling accurate and effective oil exploration.

[0107] S204: Determine the dynamic geostress of the area to be predicted according to the corrected geostress parameters.

[0108] Optionally, determining the dynamic geostress of the area to be predicted according to the corrected geostress parameter includes:

[0109] The maximum horizontal principal stress is determined based on the static Poisson's ratio, formation Biot's coefficient, rock elastic modulus, corrected geostress parameters, and formation pore pressure.

[0110] Optionally, the specific formula for determining the maximum horizontal principal stress is as follows:

[0111]

[0112] Among them, S H is the maximum principal stress of the first level, μ is the static Poisson's ratio, α is the formation Biot coefficient, E is the rock elastic modulus, ε H is the first modified geostress parameter, ε h is the second modified geostress parameter, P p is the formation pore pressure.

[0113] Here, the maximum horizontal principal stress σ H It belongs to the modified geostress. The modified principal stress is the geostress determined during the hydraulic fracturing construction process. Since the dynamically changing geostress can be predicted according to the actual formation fracture pressure during the fracturing process, the modified geostress here is the dynamic principal stress. Predicted dynamic geostress.

[0114] Optionally, the minimum principal stress σ at the prediction level h and the maximum horizontal principal stress σ H After that, the vertical stress is also predicted, which is equal to the first vertical stress predicted before fracturing, that is, σ v =S v .

[0115] The embodiment of the present application combines the geostress parameters corrected by dynamic correction parameters with the static Poisson's ratio, formation Biot coefficient, rock elastic modulus and formation pore pressure to determine the horizontal maximum principal stress, combines static and dynamic prediction data, further improves the accuracy of geostress prediction, and enables accurate and effective oil exploration.

[0116] S205: Determine a fracturing construction plan for the area to be predicted based on the dynamic geostress.

[0117] Optionally, a fracturing construction plan for the area to be predicted is determined based on the dynamic geostress, including:

[0118] Determine the fracturing construction design scheme for the area to be predicted based on the maximum horizontal principal stress;

[0119] Fracturing construction is carried out in the predicted area according to the fracturing construction design plan.

[0120] Here, the embodiment of the present application determines the fracturing construction design scheme for the area to be predicted based on the horizontal maximum principal stress. Since the determination of the horizontal maximum principal stress in the embodiment of the present application is combined with the changes in the rock fracturing process in the area to be predicted, the dynamic geostress is determined by the real fracturing data parameters, and the fixed geostress predicted before fracturing is corrected according to the dynamic geostress during the fracturing process, so that the predicted dynamic geostress is less different from the real geostress reflected in the actual fracturing process. Therefore, the fracturing construction design scheme is more suitable for the area to be predicted and can carry out more accurate oil exploration.

[0121] In a feasible implementation, the embodiment of the present application can perform fracturing construction and experiments in advance to obtain relevant parameters in real time. Figure 3 A schematic diagram of another method for real-time prediction of geostress provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the method includes:

[0122] S301: Obtaining geostress parameters of the area to be predicted.

[0123] The geostress parameters include a first geostress parameter and a second geostress parameter. The first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction.

[0124] Optionally, after obtaining the geostress parameters, static geostress may also be predicted according to the geostress parameters, where the static geostress includes a first horizontal maximum principal stress, a first horizontal minimum principal stress, and a first vertical stress.

[0125] The specific formulas for predicting the first horizontal maximum principal stress, the first horizontal minimum principal stress, and the first vertical stress are as follows:

[0126]

[0127] Among them, the above S v is the first vertical stress, S H is the maximum principal stress at the first level, S h is the first level minimum principal stress, H0 is the depth of the logging starting point, ρ0(h) is the density of the unlogged section at the depth H0, ρ(h) is the logging density at the depth H, g is the gravitational acceleration, μ is the static Poisson's ratio, α is the formation Biot coefficient, E is the rock elastic modulus, ε H is the strain coefficient, ε, along the direction of the maximum horizontal principal stress. h is the strain coefficient along the horizontal minimum principal stress direction, P p is the formation pore pressure.

[0128] Optionally, the specific method of predicting geostress based on geostress parameters is to predict geostress based on geostress parameters and a direct calculation method of linear elastic theory. The main applied models may be, but are not limited to, the following: Mohr-Columb model, uniaxial strain model, including Matthews&Kelly model, Anderson model and Newberry model, etc., Huang Rongzun model of Petroleum University and combined spring model. The specific model adopted by the direct calculation method of linear elastic theory is not limited here.

[0129] S302: Perform fracturing construction on the predicted area to obtain the formation fracture pressure; perform actual measurement on other wells in the oil and gas reservoirs in the predicted area to obtain the formation pore pressure; perform rock mechanics experiments on the predicted area to obtain rock mechanics parameters.

[0130] Among them, rock mechanics parameters include formation porosity, rock contact porosity and rock tensile strength.

[0131] Specifically, the formation fracture pressure P b It is measured in the well during hydraulic fracturing. The formation pore pressure P p It is obtained based on the actual measurements of other wells in oil and gas reservoirs. Rock contact porosity and rock tensile strength σ f It is obtained from rock mechanics experiments, where the rock contact porosity Formation porosity There is a specific relationship. If the degree of rock cementation is low, the rock contact porosity tends to 1. If the degree of rock cementation is high, the rock contact porosity tends to the formation porosity. The specific value needs to be obtained based on rock mechanics experiments.

[0132] S303: Determine a first vertical stress according to the geostress parameter.

[0133] The first vertical stress is the vertical stress predicted according to the ground stress parameter.

[0134] S304: Calculate and obtain correction parameters based on formation fracture pressure, formation pore pressure, rock mechanics parameters and the first vertical stress.

[0135] S305: Correcting the geostress parameter according to the correction parameter to obtain the corrected geostress parameter.

[0136] S306: Determine the dynamic geostress of the area to be predicted according to the corrected geostress parameters.

[0137] S307: Determine a fracturing construction plan for the area to be predicted based on the dynamic geostress.

[0138] Among them, the implementation method of steps S305-S307 is the same as the implementation method of steps S303-S305, and the embodiment of the present application does not make specific limitations on this.

[0139] The embodiment of the present application obtains the formation breakdown pressure from the fracturing data, obtains the formation pore pressure based on actual measurements of other wells in the oil and gas reservoir, and obtains rock mechanics parameters including formation porosity, rock contact porosity and rock tensile strength based on rock mechanics experiments. The real fracturing data parameters of the formation during the fracturing process are utilized, and the real geostress of the formation can be determined according to the real formation breakdown pressure that changes during the fracturing process. The fixed geostress predicted before fracturing can be dynamically corrected. According to the measurement and acquisition of the above experiments, real-time and accurate dynamic parameters are obtained, thereby improving the accuracy of determining the correction parameters and further improving the accuracy of determining the geostress.

[0140] Figure 4 A schematic diagram of the structure of a real-time prediction device for geostress provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, the device of the embodiment of the present application includes: an acquisition module 401, a first determination module 402, a correction module 403, a second determination module 404 and a processing module 405. The real-time prediction device for geostress here can be the above-mentioned processor 102 itself, or a chip or integrated circuit that realizes the function of the processor 102. It should be noted here that the division of the acquisition module 401, the first determination module 402, the correction module 403, the second determination module 404 and the processing module 405 is only a division of logical functions, and the two can be physically integrated or independent.

[0141] The acquisition module 401 is used to acquire the geostress parameters of the area to be predicted, the geostress parameters include a first geostress parameter and a second geostress parameter, the first geostress parameter is a tectonic strain coefficient along the direction of the maximum horizontal principal stress, and the second geostress parameter is a tectonic strain coefficient along the direction of the minimum horizontal principal stress;

[0142] A first determination module 402 is used to determine correction parameters, where the correction parameters are calculated using construction parameters obtained during fracturing construction;

[0143] A correction module 403 is used to correct the geostress parameter according to the correction parameter to obtain the corrected geostress parameter;

[0144] The second determination module 404 is used to determine the dynamic geostress of the area to be predicted according to the corrected geostress parameter;

[0145] The processing module 405 is used to determine the fracturing construction plan of the area to be predicted according to the dynamic ground stress.

[0146] Optionally, the construction parameters include formation fracture pressure, formation pore pressure and rock mechanics parameters;

[0147] The first determination module 402 is specifically used to determine the first vertical stress according to the ground stress parameter;

[0148] The correction parameters are calculated based on the formation fracture pressure, formation pore pressure, rock mechanics parameters and the first vertical stress.

[0149] Optionally, before the first determination module 402 calculates and obtains the correction parameter according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress, the apparatus further includes:

[0150] Construction module 406, used to perform fracturing construction on the predicted area to obtain the formation fracture pressure;

[0151] The actual measurement module 407 is used to measure other wells in the oil and gas reservoirs in the predicted area to obtain the formation pore pressure;

[0152] The experimental module 408 is used to perform rock mechanics experiments on the predicted area to obtain rock mechanics parameters, wherein the rock mechanics parameters include formation porosity, rock contact porosity and rock tensile strength.

[0153] Optionally, the correction module 403 is specifically used for:

[0154] Determine the first level minimum principal stress according to the ground stress parameter;

[0155] The first horizontal minimum principal stress is made equal to the correction parameter, and the first geostress parameter is made the first multiple of the second geostress parameter, to obtain the corrected first geostress parameter and the corrected second geostress parameter, wherein the first multiple is greater than 1 and less than 10.

[0156] Optionally, the second determining module 404 is specifically configured to:

[0157] The maximum horizontal principal stress is determined based on the static Poisson's ratio, formation Biot's coefficient, rock elastic modulus, corrected geostress parameters, and formation pore pressure.

[0158] Optionally, the processing module 405 is specifically used to determine a fracturing construction design scheme for the area to be predicted according to the maximum horizontal principal stress;

[0159] Fracturing construction is carried out in the predicted area according to the fracturing construction design plan.

[0160] Based on the same inventive concept, an embodiment of the present invention also provides a real-time prediction device for ground stress. Figure 5 FIG. 1 is a schematic diagram of the structure of a real-time prediction device for geostress in an embodiment of the present invention, see Figure 5 As shown, the real-time prediction device 50 for geostress may include: at least one processor 501; and at least one memory 502 and a bus 503 connected to the processor 501; wherein the processor 501 and the memory 502 communicate with each other via the bus 503; the processor 501 is used to call the program instructions in the memory 502 to execute the real-time prediction method for geostress in one or more of the above-mentioned embodiments.

[0161] It should be noted that the description of the above embodiment of the real-time prediction device for geostress is similar to the description of the above method embodiment, and has similar beneficial effects as the method embodiment. For technical details not disclosed in the embodiment of the real-time prediction device for geostress of the embodiment of the present invention, please refer to the description of the method embodiment of the present invention for understanding.

[0162] The real-time prediction device for geostress in the embodiment of the present application can be used to execute the technical solutions in the above-mentioned method embodiments of the present application. Its implementation principles and technical effects are similar and will not be repeated here.

[0163] An embodiment of the present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement any of the above-mentioned real-time prediction methods for geostress.

[0164] An embodiment of the present invention further provides a computer program product, including a computer program. When the computer program is executed by a processor, the real-time prediction method of geostress as described above is implemented.

[0165] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0166] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0167] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

Claims

1. A real-time prediction method for geostress, characterized in that: include: Acquire geostress parameters of the area to be predicted, wherein the geostress parameters include a first geostress parameter and a second geostress parameter, wherein the first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction; Determining correction parameters, including: determining a first vertical stress according to the ground stress parameter; calculating a correction parameter according to the construction parameters obtained during the hydraulic fracturing construction and the first vertical stress, wherein the correction parameter is a dynamic horizontal minimum principal stress determined during the hydraulic fracturing construction; wherein the construction parameters include formation fracture pressure, formation pore pressure, and rock mechanics parameters; The in-situ stress parameter is corrected according to the correction parameter to obtain the corrected in-situ stress parameter, including: determining a first horizontal minimum principal stress according to the in-situ stress parameter; making the first horizontal minimum principal stress equal to the correction parameter, and making the first in-situ stress parameter a first multiple of the second in-situ stress parameter, to obtain a corrected first in-situ stress parameter and a corrected second in-situ stress parameter, wherein the first multiple is greater than 1 and less than 10, and the specific value of the first multiple is obtained through an in-situ stress test experiment of a rock sample in a to-be-predicted area during a hydraulic fracturing construction process; Determining the dynamic geostress of the area to be predicted according to the corrected geostress parameter; A fracturing construction plan for the area to be predicted is determined according to the dynamic geostress.

2. The method according to claim 1, characterized in that Before obtaining the correction parameter by calculating according to the formation fracture pressure, the formation pore pressure, the rock mechanics parameter and the first vertical stress, the method further includes: Performing fracturing construction on the area to be predicted to obtain formation fracture pressure; Conducting actual measurements on other wells in the oil and gas reservoirs in the area to be predicted to obtain formation pore pressure; A rock mechanics experiment is performed on the area to be predicted to obtain rock mechanics parameters, wherein the rock mechanics parameters include formation porosity, rock contact porosity and rock tensile strength.

3. The method according to any one of claims 1 or 2, characterized in that: Determining the dynamic geostress of the area to be predicted according to the corrected geostress parameter includes: The maximum horizontal principal stress is determined according to the static Poisson's ratio, the formation Biot coefficient, the rock elastic modulus, the corrected in-situ stress parameter, and the formation pore pressure.

4. The method according to any one of claims 1 or 2, characterized in that: The method of determining the fracturing construction scheme of the area to be predicted according to the dynamic geostress comprises: Determine a fracturing construction design scheme for the area to be predicted according to the horizontal maximum principal stress; The fracturing construction is performed on the area to be predicted according to the fracturing construction design plan.

5. A real-time prediction device for geostress, applied to the real-time prediction method for geostress according to any one of claims 1 to 4, characterized in that: include: An acquisition module, used to acquire geostress parameters of the area to be predicted, wherein the geostress parameters include a first geostress parameter and a second geostress parameter, wherein the first geostress parameter is a tectonic strain coefficient along a horizontal maximum principal stress direction, and the second geostress parameter is a tectonic strain coefficient along a horizontal minimum principal stress direction; A first determination module is used to determine correction parameters, where the correction parameters are calculated using construction parameters obtained during fracturing construction; A correction module, used for correcting the geostress parameter according to the correction parameter to obtain a corrected geostress parameter; A second determination module is used to determine the dynamic geostress of the area to be predicted according to the corrected geostress parameter; A processing module is used to determine a fracturing construction plan for the area to be predicted according to the dynamic ground stress.

6. A real-time prediction device for ground stress, characterized in that: include: at least one processor and memory; The memory stores computer-executable instructions; The at least one processor executes the computer-executable instructions stored in the memory, so that the at least one processor executes the real-time prediction method for geostress according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions. When the processor executes the computer-executable instructions, the real-time prediction method for geostress according to any one of claims 1 to 4 is implemented.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the real-time prediction method for geostress according to any one of claims 1 to 4 is implemented.

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