Method and device for predicting five key engineering parameters of horizontal well for shale oil and gas reservoir

Abstract

The invention discloses a method and device for predicting five key engineering parameters of a horizontal well facing a shale oil and gas reservoir, and the method comprises the steps: building a shale oil and gas theoretical rock physical model according to the shale oil and gas geology and rock physical characteristics; in combination with horizontal well element logging and conventional logging data, based on the improved CPS model and the corrected overlying formation pressure and hydrostatic pressure, formation pressure prediction of the horizontal well is achieved; on the basis of HTI anisotropic medium theory assumption, a maximum horizontal principal stress prediction model and a minimum horizontal principal stress prediction model are constructed, and maximum horizontal principal stress prediction and minimum horizontal principal stress prediction of the horizontal well are achieved; on the basis of the constructed anisotropic fracture pressure prediction model, fracture pressure prediction of the horizontal well is achieved; and realizing collapse pressure prediction of the horizontal well on the basis of a collapse pressure prediction model constructed based on a Mohr-Coulomb criterion. According to the method, fine description and characterization of rock mechanics characteristics of the horizontal well can be achieved, and efficient and intelligent fracturing of the shale oil and gas horizontal well is supported.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of petroleum geophysical exploration and development, and more particularly, to a method and device for predicting five key engineering parameters of a horizontal well for shale oil and gas reservoirs. BACKGROUND

[0002] For the exploration and development of unconventional shale oil and gas reservoirs, large-scale horizontal wells and well group fracturing are the main forms of exploration and development. Conventional shale oil and gas key engineering parameter prediction is mainly based on pilot well drilling (vertical well), which can only describe the rock mechanics characteristics of the shale reservoir of different layer series in the vertical direction, and cannot finely depict and describe the fracturing geology and engineering parameter characteristics of each section and cluster of the horizontal well. Therefore, it is urgent to develop a key engineering parameter prediction technology for horizontal wells for shale oil and gas reservoirs to guide efficient and intelligent fracturing of shale oil and gas. SUMMARY

[0003] The purpose of the present application is to provide a method and device for predicting five key engineering parameters of a horizontal well for shale oil and gas reservoirs, to achieve fine description and characterization of the rock mechanics characteristics of each section and cluster of the horizontal well, and to guide fine segmentation and clustering of the horizontal well, fracturing scheme optimization, and efficient and intelligent fracturing of shale oil and gas horizontal wells.

[0004] To achieve the above purpose, in a first aspect, the present application provides a method for predicting five key engineering parameters of a horizontal well for shale oil and gas reservoirs, comprising:

[0005] According to the geology and rock physics characteristics of shale oil and gas, a theoretical rock physics model of shale oil and gas is constructed to obtain the elastic parameters, anisotropy parameters and stiffness matrix of the rock;

[0006] Based on the theoretical rock physics model of shale oil and gas and combined with a geomechanical model, five key engineering parameters of the horizontal well are predicted, including:

[0007] Based on the improved CPS model, the corrected overburden pressure and hydrostatic pressure, the formation pressure of the horizontal well is predicted by combining the element logging and conventional logging data of the horizontal well;

[0008] Based on the HTI anisotropic medium theory assumption, a maximum and minimum horizontal principal stress prediction model is constructed to predict the maximum and minimum horizontal principal stresses of the horizontal well;

[0009] Based on the constructed anisotropic fracture pressure prediction model, the fracture pressure of the horizontal well is predicted;

[0010] Based on the collapse pressure prediction model constructed based on the Mohr-Coulomb criterion, the collapse pressure of the horizontal well is predicted.

[0011] Optionally, the shale oil and gas theoretical petrophysical model is constructed according to shale oil and gas geology and petrophysical characteristics, and the shale oil and gas theoretical petrophysical model comprises the following steps:

[0012] According to the unconventional shale oil and gas geological characteristics, the theoretical petrophysical model is constructed step by step, and the overall technical process is as follows:

[0013] Based on the Vogit-Reuss-Hill average theory, the equivalent modulus and pore fluid modulus of different types of rock minerals are calculated;

[0014] Based on the Wood formula, the mixed volume modulus of different types of fluids is calculated;

[0015] Based on the differential equivalent medium model, the pores are implanted into the matrix minerals, and the bulk modulus and shear modulus of the dry rock skeleton are calculated;

[0016] Based on the Backus average theory, the VTI interbedded background medium elastic matrix is constructed;

[0017] Based on the Schoenberg linear sliding theory, high-angle fractures are implanted;

[0018] Through the Brown-korringna anisotropic fluid replacement theory, the fluid is implanted, and the bulk modulus and shear modulus of the saturated rock are calculated;

[0019] According to the Thomsen weak anisotropy theory assumption, the rock elastic parameters, Thomsen weak anisotropy parameters and elastic stiffness matrix are obtained.

[0020] Optionally, the shale oil and gas theoretical petrophysical model is constructed according to shale oil and gas geology and petrophysical characteristics, and the shale oil and gas theoretical petrophysical model comprises the following steps:

[0021] The density logging curves of the horizontal well and the pilot hole are comprehensively utilized, and the overburden pressure Pov and the hydrostatic pressure Ph of the horizontal well are calculated based on the overburden pressure and the hydrostatic pressure calculation formula, wherein the overburden pressure and the hydrostatic pressure calculation formula is as follows:

[0022]

[0023] In the formula, Pov and Ph represent the overburden pressure and the hydrostatic pressure respectively, ρ(z) and ρ w (z) represent the rock density and the liquid density under different depth conditions respectively, g represents the acceleration of gravity, and z represents the depth;

[0024] Through the element logging data of the horizontal well, the acoustic time difference under the normal compaction trend of the horizontal well is calculated combined with the improved CPS model;

[0025] The Eaton formula is used to calculate the predicted formation pressure of the horizontal well based on the overburden pressure, the hydrostatic pressure, the normal compaction trend acoustic travel time and the actually measured acoustic travel time.

[0026] P p = P ov - (P ov - P h )(Δt n / Δt) n

[0027] In the formula, Pp, Pov and Ph represent the formation pressure, the overburden pressure and the hydrostatic pressure respectively, Δt n represents the normal compaction trend acoustic travel time, and Δt represents the actually measured acoustic travel time.

[0028] Optionally, the element logging data of the horizontal well comprises clay minerals, siliceous minerals, calcareous minerals, organic matter content, porosity and water saturation.

[0029] The acoustic travel time of the horizontal well under the normal compaction trend is calculated based on the element logging data of the horizontal well and the improved CPS model, which comprises the following steps.

[0030] The stiffness matrix of the "wet clay" mixture composed of the pore fluid and the clay particles is calculated.

[0031] The stiffness matrix of the sandy mixture composed of the siliceous minerals, the calcareous minerals and other hard minerals is calculated.

[0032] The stiffness matrix of the equivalent medium composed of the wet clay-sandy mixture-organic matter is calculated based on the Backus average formula.

[0033] The stiffness matrix of the equivalent shale is converted into the acoustic travel time under the normal compaction trend.

[0034] In the formula, the expression of the elastic stiffness matrix of the equivalent shale is as follows.

[0035]

[0036] C 12 = C 11 -<c 11 >+<c 12 >,

[0037]

[0038] C 66 =<c 66 >;

[0039] In the formula, C ijdenotes the elastic stiffness components of the equivalent shale, i = 1, 3, 4, 6, j = 1, 2, 3, 4, 6, c ij denotes the elastic stiffness components of each phase, and the angle brackets <·> denote the volume-weighted average of the properties within.

[0040] Optionally, based on the HTI anisotropic medium theory assumption, a maximum and minimum horizontal principal stress prediction model is constructed to realize the prediction of the maximum and minimum horizontal principal stresses of the horizontal well, comprising:

[0041] Obtain the formation pressure and overburden pressure calculated based on the horizontal well;

[0042] Based on the conversion relationship between the elastic parameters and the rock mechanics parameters, the Young's modulus and Poisson's ratio of the horizontal well are calculated and obtained;

[0043] Based on the Schoenberg linear slip theory of the HTI medium assumption, the fracture normal compliance and the fracture tangential compliance are calculated and obtained;

[0044] Based on the rock physics experimental measurement, the tectonic strain coefficient is obtained;

[0045] Based on the calculated overburden pressure, formation pressure, Young's modulus, Poisson's ratio, fracture normal compliance, fracture tangential compliance, and tectonic strain coefficient, the maximum and minimum horizontal principal stress prediction values of the horizontal well are obtained through the following calculation formula:

[0046]

[0047] In the formula: S h is the minimum horizontal principal stress, S H is the maximum horizontal principal stress, S V is the overburden pressure, P p is the formation pressure, E is the Young's modulus, σ is the Poisson's ratio, Z n is the fracture normal compliance, Z t is the fracture tangential compliance, ε H is the tectonic strain coefficient.

[0048] Optionally, based on the constructed anisotropic fracture pressure prediction model, the fracture pressure prediction of the horizontal well is realized, comprising:

[0049] Based on the rock physics experimental measurement, the tectonic stress coefficient is obtained;

[0050] Based on the rock physics statistical relationship of the shale oil and gas working area, the tensile strength is calculated and obtained;

[0051] Obtain the formation pressure and overburden pressure calculated based on the horizontal well;

[0052] An elastic stiffness matrix element of equivalent shale is obtained based on a shale oil and gas reservoir petrophysical modeling;

[0053] A fracture pressure prediction value of the horizontal well is calculated based on the tectonic stress coefficient, the tensile strength, the formation pressure, the overburden pressure, and the anisotropic fracture pressure prediction model.

[0054] The anisotropic fracture pressure prediction model is expressed as:

[0055]

[0056] P = S + C + K f The fracture pressure is P p The formation pressure is k, the tectonic stress coefficient is S, the overburden pressure is P P The formation pressure is S t The tensile strength is C 13 And C 33 The stiffness matrix elements of the equivalent shale.

[0057] Optionally, the collapse pressure prediction model constructed based on the Mohr-Coulomb criterion realizes collapse pressure prediction of the horizontal well, and includes:

[0058] The cohesion and the internal friction angle are calculated based on a shale oil and gas reservoir petrophysical empirical relationship.

[0059] The maximum and minimum horizontal principal stresses are obtained based on the horizontal well calculation.

[0060] The collapse pressure prediction value of the horizontal well is calculated based on the cohesion, the internal friction angle, the maximum and minimum horizontal principal stresses, and the collapse pressure prediction model constructed by the Mohr-Coulomb criterion.

[0061] The collapse pressure prediction model is expressed as:

[0062]

[0063] K = cot (π / 4-φ / 2)

[0064] P = S + C + K m The collapse pressure is S h The minimum horizontal principal stress is S H The maximum horizontal principal stress is C, the cohesion is φ, and the internal friction angle is φ.

[0065] In a second aspect, the present application provides an electronic device, which comprises:

[0066] At least one processor; and

[0067] a memory in communication with the at least one processor; wherein

[0068] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction method of the first aspect.

[0069] In a third aspect, the present application provides a non-transitory computer readable storage medium storing computer instructions for causing a computer to perform the shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction method of the first aspect.

[0070] In a fourth aspect, the present application provides a shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction device, comprising:

[0071] A petrophysical model construction module is configured to construct a shale oil and gas theoretical petrophysical model according to shale oil and gas geology and petrophysical characteristics, and obtain elastic parameters, anisotropy parameters and stiffness matrix of rocks;

[0072] A five key engineering parameter prediction module is configured to, based on the shale oil and gas theoretical petrophysical model, combine a geomechanical model, and develop shale oil and gas five key engineering parameter prediction, specifically including:

[0073] A formation pressure prediction submodule is configured to, based on an improved CPS model, a corrected overburden pressure and hydrostatic pressure, realize horizontal well formation pressure prediction by combining horizontal well element logging and conventional logging data;

[0074] A horizontal principal stress prediction submodule is configured to, based on HTI anisotropic medium theory assumption, construct a maximum and minimum horizontal principal stress prediction model, and realize maximum and minimum horizontal principal stress prediction of a horizontal well;

[0075] A fracture pressure prediction submodule is configured to, based on the constructed anisotropic fracture pressure prediction model, realize horizontal well fracture pressure prediction;

[0076] A collapse pressure prediction submodule is configured to, based on a collapse pressure prediction model constructed based on the Mohr-Coulomb criterion, realize horizontal well collapse pressure prediction.

[0077] The present application has the following beneficial effects:

[0078] The present application can fully utilize the horizontal well data, finely describe the rock mechanics environment of the wellbore, effectively guide the segmented and clustered horizontal well, the one-segment-one-strategy and efficient and intelligent fracturing, and support the high-quality exploration and development of shale oil and gas.

[0079] The system of the present application has other characteristics and advantages that will be apparent from and / or set forth in the accompanying drawings and the following detailed description of the application, as they are collectively used to explain certain principles of the application. BRIEF DESCRIPTION OF DRAWINGS

[0080] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description of exemplary embodiments of the present application taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout the several views.

[0081] Figure 1 A step diagram of a horizontal well five key engineering parameter prediction method for shale oil and gas reservoirs is shown.

[0082] Figure 2 A work area location and work area target layer structure base map of well A is shown.

[0083] Figure 3 A horizontal well element logging (mineral composition) curve graph of well A is shown.

[0084] Figure 4 A five key engineering parameter prediction graph of well A is shown.

[0085] Figure 5 An engineering parameter real drilled value and measured value comparison graph of well A at a measured depth of 5200 meters is shown.

[0086] Figure 6 A segmented schematic diagram based on the five key engineering parameter prediction of the horizontal well of well A is shown. DETAILED DESCRIPTION

[0087] The eye guide well for shale oil and gas can only represent the longitudinal different layer shale reservoir elasticity and rock mechanics characteristics, and cannot meet the needs of fine characterization and description of the rock mechanics characteristics of each segment and each cluster of the shale oil and gas horizontal well, the present application proposes a horizontal well five key engineering parameter prediction method and device for shale oil and gas reservoirs, which can fully utilize the horizontal well data, finely describe and represent the rock mechanics characteristics of each segment and each cluster of the horizontal well, guide the fine segmentation and clustering of the horizontal well, optimize the fracturing scheme, and support the efficient and intelligent fracturing of the shale oil and gas horizontal well.

[0088] The application will be described in greater detail below with reference to the drawings. While the preferred embodiments of the application are shown in the drawings, it is understood that the application can be practiced in various forms and should not be limited to the embodiments set forth in the drawings. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0089] Embodiment 1

[0090] As Figure 1 shown, the embodiment provides a shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction method, including:

[0091] S1: According to the shale oil and gas geology and petrophysical characteristics, a shale oil and gas theoretical petrophysical model is constructed to obtain the elastic parameters, anisotropy parameters and stiffness matrix of the rock;

[0092] This step constructs a theoretical petrophysical model in steps according to the unconventional shale oil and gas geological characteristics, and the specific process is as follows:

[0093] S101: Based on the Vogit-Reuss-Hill average theory, the equivalent modulus and pore fluid modulus of different types of rock minerals are calculated;

[0094] S102: Based on the Wood formula, the mixed volume modulus of different types of fluids is calculated;

[0095] S103: Based on the differential equivalent medium model, the pores are implanted into the matrix mineral, and the bulk modulus and shear modulus of the dry rock skeleton are calculated;

[0096] S104: Based on the Backus average theory, a VTI interbedded background medium elastic matrix is constructed;

[0097] S105: Based on the Schoenberg linear sliding theory, high-angle fractures are implanted;

[0098] S106: Through the Brown-korringna anisotropic fluid replacement theory, the fluid is implanted, and the bulk modulus and shear modulus of the saturated rock are calculated;

[0099] S107: According to the Thomsen weak anisotropy theory assumption, the rock elastic parameters, Thomsen weak anisotropy parameters and elastic stiffness matrix are obtained. Based on the shale oil and gas theoretical petrophysical model, combined with the geomechanical model, the five key engineering parameters of the horizontal well are predicted, including the formation pressure, the maximum horizontal principal stress, the minimum horizontal principal stress, the fracture pressure and the collapse pressure.

[0100] S2: Based on the improved CPS model, the corrected overburden pressure and hydrostatic pressure, the formation pressure prediction of the horizontal well is realized by combining the element logging data of the horizontal well and the conventional logging data;

[0101] Specifically, the logging formation pressure is calculated based on the Eaton formula in this step:

[0102] P p = P ov -(P ov -P h )(Δt n / Δt) n (1)

[0103] In the formula, Pp, Pov and Ph represent the formation pressure, the overburden pressure and the hydrostatic pressure respectively, Δt n represents the acoustic travel time under normal compaction, and Δt represents the actually measured acoustic travel time.

[0104] The specific calculation process of this step is as follows:

[0105] S201: The overburden pressure and the hydrostatic pressure corresponding to the horizontal well are calculated based on the overburden pressure and the hydrostatic pressure calculation formula by comprehensively utilizing the density logging curves of the horizontal well and the pilot hole.

[0106]

[0107] In the formula, Pov and Ph represent the overburden pressure and the hydrostatic pressure respectively, ρ(z) and ρ w (z) represent the rock density and the liquid density under different depth conditions respectively, g represents the acceleration of gravity, and z represents the depth.

[0108] S202: The acoustic travel time under the normal compaction trend of the horizontal well is calculated by the element logging data of the horizontal well, including the clay mineral, the siliceous mineral, the calcareous mineral, the organic matter content, the porosity, the water saturation and the like, and the improved CPS model, and the specific method is as follows:

[0109] (1) The stiffness matrix of the "wet clay" mixture composed of the pore fluid and the clay particles is calculated;

[0110] (2) The stiffness matrix of the sandy mixture composed of the siliceous mineral, the calcareous mineral and the like is calculated;

[0111] (3) The stiffness matrix of the equivalent medium composed of the wet clay-sandy mixture-organic matter three phases is calculated based on the Backus average formula;

[0112] (4) The stiffness matrix of the equivalent shale is converted into the acoustic travel time under the normal compaction trend.

[0113] wherein the stiffness matrix of the equivalent shale is:

[0114]

[0115] wherein: C ij represents the elastic stiffness component of the equivalent shale, c ij is the elastic stiffness component of each phase, and the angle brackets <·> represent the weighted average of the properties within them according to the volume ratio.

[0116] S203: Based on the Eaton formula, the overburden pressure calculated above, the acoustic travel time under normal compaction tendency, and the actually measured acoustic travel time, the predicted value of the formation pressure of the horizontal well can be calculated.

[0117] S3: Based on the HTI anisotropic medium theory assumption, a maximum and minimum horizontal principal stress prediction model is constructed to realize the prediction of the maximum and minimum horizontal principal stresses of the horizontal well.

[0118] This step is based on the HTI medium (transversely isotropic medium with horizontal symmetry axis) assumption to calculate the ground stress parameters, including the maximum and minimum horizontal principal stresses.

[0119] This step specifically includes:

[0120] S301: Obtain the overburden pressure and the formation pressure of the horizontal well calculated based on the Eaton formula above;

[0121] S302: Based on the elastic parameter and rock mechanics parameter conversion relationship, the Young's modulus E and Poisson's ratio σ of the horizontal well are calculated;

[0122] S303: Based on the Schoenberg linear slip theory of the HTI medium assumption, the fracture normal compliance Z n and the fracture tangential compliance Z t are calculated.

[0123] S304: Based on the rock physics experimental measurement, the tectonic strain coefficient ε H is obtained.

[0124] S305: Based on the constructed maximum and minimum horizontal principal stress calculation formula, the predicted values of the maximum and minimum horizontal principal stresses of the horizontal well can be obtained:

[0125]

[0126] wherein: S h is the minimum horizontal principal stress, S H is the maximum horizontal principal stress, and S V is the overburden pressure, Pp P is the formation pressure, E is the Young's modulus, σ is the Poisson's ratio, Z n is the normal flexibility of the fracture, Z t is the tangential flexibility of the fracture, ε H is the tectonic strain coefficient.

[0127] S4: based on the constructed anisotropic fracturing pressure prediction model, realizing the fracturing pressure prediction of the horizontal well;

[0128] The step specifically includes:

[0129] S401: obtaining the tectonic stress coefficient k based on the rock physical experimental measurement,

[0130] S402: obtaining the tensile strength S based on the rock physical statistical relationship of the shale oil and gas working area, t

[0131] S403: obtaining the formation pressure P and the overburden pressure S based on the horizontal well, P

[0132] S404: obtaining the rock stiffness matrix elements C and C based on the rock physical modeling of the shale oil and gas reservoir, 13 33

[0133] S405: based on the constructed anisotropic fracturing pressure prediction model, the fracturing pressure prediction value of the horizontal well can be calculated:

[0134]

[0135] In the formula: P f is the fracturing pressure, P p is the formation pressure, k is the tectonic stress coefficient, S is the overburden pressure, P P is the formation pressure, S t is the tensile strength, C 13 and C 33 are the stiffness matrix elements of the shale, respectively.

[0136] S5: based on the collapse pressure prediction model constructed based on the Mohr-Coulomb criterion, realizing the collapse pressure prediction of the horizontal well.

[0137] The step specifically includes:

[0138] S501: calculating the cohesion C and the internal friction angle φ based on the rock physical empirical relationship of the shale oil and gas reservoir;

[0139] S502: obtaining the maximum horizontal principal stress S H and the minimum horizontal principal stress S h based on the horizontal well;​​​​

[0140] S503: Constructing a collapse pressure prediction model based on the Mohr-Coulomb criterion, and calculating the collapse pressure prediction value of the horizontal well:

[0141]

[0142] K = cot (π / 4-φ / 2) (7)

[0143] In the formula: P m Collapse pressure, S h is the minimum horizontal principal stress, S H is the maximum horizontal principal stress, C is the cohesion, and φ is the internal friction angle.

[0144] Based on the above prediction results, the five key engineering parameters of the shale oil and gas horizontal well, i.e. formation pressure, maximum horizontal principal stress, minimum horizontal principal stress, fracture pressure and collapse pressure, are predicted.

[0145] Example 2

[0146] This example illustrates the effectiveness of the method of the present application by using actual data of a shale gas work area in Sichuan Basin. The main steps of the method of this example include: ①. Constructing a shale oil and gas theoretical rock physics model; ②. Based on the improved CPS model, the formation pressure of the horizontal well is predicted; ③. Based on the HTI medium theory assumption, the maximum and minimum horizontal principal stresses of the horizontal well are predicted; ④. Based on the anisotropic fracture pressure prediction model, the fracture pressure of the horizontal well is predicted; ⑤. Based on the collapse pressure prediction model, the collapse pressure of the horizontal well is predicted; ⑥. Based on the comprehensive interpretation of the five key engineering parameters of the horizontal well, the segmented cluster and one-segment-one-strategy are guided.

[0147] The well A of this experiment is located in the southeast sag area of Sichuan Basin, and the horizontal well mainly drills through deep shale target reservoirs Figure 2 The element logging curve of the horizontal well, i.e. the input data Figure 3 for the prediction of the five key engineering parameters, specifically includes: clay content, siliceous content, calcareous content, organic matter content, porosity, etc. Combined with rock physics and geomechanics models, the five key engineering parameters of the horizontal well are predicted Figure 4 , specifically including: pore pressure, maximum horizontal principal stress, minimum horizontal principal stress, fracture pressure and collapse pressure. Through the comparison chart Figure 5 of the engineering parameter real drilling value and the measured value of well A at the measurement depth of 5200 meters, it can be obtained that the overall prediction coincidence rate of the five key engineering parameters of the horizontal well reaches 95.8%, which verifies the accuracy and rationality of the prediction results of the present application. Further based on the prediction results of the five key engineering parameters of the horizontal well, fine segmented cluster is developed, such as Figure 6As shown, the horizontal well is divided into 24 horizontal sections, which provides reasonable basis and guidance for subsequent efficient fracturing.

[0148] It can be seen from the above analysis that the five key engineering parameter predictions of the horizontal well, specifically including formation pressure, maximum horizontal principal stress, minimum horizontal principal stress, fracture pressure and collapse pressure, can fully utilize the horizontal well data, finely describe the rock mechanics environment of the wellbore, effectively guide the segmentation and clustering of the horizontal well, the "one section one strategy" and efficient and intelligent fracturing, and support high-quality exploration and development of shale oil and gas.

[0149] Embodiment 3

[0150] The embodiment provides a device for predicting five key engineering parameters of a horizontal well for a shale oil and gas reservoir, which comprises:

[0151] A rock physics model construction module is configured to construct a shale oil and gas theoretical rock physics model according to shale oil and gas geology and rock physics characteristics, and obtain elastic parameters, anisotropy parameters and stiffness matrix of rocks;

[0152] A five key engineering parameter prediction module is configured to predict five key engineering parameters of the horizontal well based on the shale oil and gas theoretical rock physics model and in combination with a geomechanical model, specifically including:

[0153] A formation pressure prediction submodule is configured to predict formation pressure of the horizontal well based on an improved CPS model, corrected overburden pressure and hydrostatic pressure in combination with horizontal well element logging and conventional logging data;

[0154] A horizontal principal stress prediction submodule is configured to construct a maximum and minimum horizontal principal stress prediction model based on an HTI anisotropic medium theory assumption, and predict maximum and minimum horizontal principal stress of the horizontal well;

[0155] A fracture pressure prediction submodule is configured to predict fracture pressure of the horizontal well based on a constructed anisotropic fracture pressure prediction model;

[0156] A collapse pressure prediction submodule is configured to predict collapse pressure of the horizontal well based on a collapse pressure prediction model constructed based on the Mohr-Coulomb criterion.

[0157] Embodiment 4

[0158] The embodiment provides an electronic device, which comprises:

[0159] at least one processor; and

[0160] a memory in communication with the at least one processor; wherein

[0161] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction method described in the above embodiments.

[0162] An electronic device according to an embodiment of the disclosure includes a memory and a processor. Specifically, the memory can include one or more computer program products that can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM), cache memory, and / or the like. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, and / or the like.

[0163] The processor can be a central processing unit (CPU) or other form of processing unit having data processing and / or instruction execution capabilities, and can control other components in the electronic device to perform desired functions. In an embodiment of the disclosure, the processor is configured to execute the computer-readable instructions stored in the memory.

[0164] Those skilled in the art will understand that, in order to solve the technical problem of how to obtain a good user experience effect, the embodiment can also include well-known structures such as a communication bus, an interface, and the like, which should also be included in the protection scope of the disclosure.

[0165] Detailed descriptions of the embodiments can refer to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.

[0166] Embodiment 5

[0167] The embodiment provides a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the shale oil and gas reservoir-oriented horizontal well five key engineering parameter prediction method described in the above embodiments.

[0168] According to an embodiment of the disclosure, a computer-readable storage medium has non-transitory computer-readable instructions stored thereon. When the non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the method of the above embodiments of the disclosure are performed.

[0169] The above computer readable storage medium includes, but is not limited to, an optical storage medium (for example, a CD-ROM and a DVD), a magneto-optical storage medium (for example, an MO), a magnetic storage medium (for example, a magnetic tape or a moving hard disk), a medium having a built-in rewritable nonvolatile memory (for example, a memory card), and a medium having a built-in ROM (for example, a ROM cartridge).

[0170] The above has described the embodiments of the present application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for predicting five key engineering parameters of horizontal wells in shale oil and gas reservoirs, characterized in that, include: Based on the geological and rock physical characteristics of shale oil and gas, a theoretical rock physical model for shale oil and gas is constructed to obtain the elastic parameters, anisotropic parameters and stiffness matrix of the rock. Based on the aforementioned shale oil and gas theoretical rock physics model, combined with the geomechanical model, five key engineering parameters for horizontal wells are predicted, including: Combining elemental logging and conventional logging data from horizontal wells, and based on the improved CPS model, corrected overlying formation pressure, and hydrostatic pressure, formation pressure prediction for horizontal wells is achieved. Based on the assumptions of HTI anisotropic media theory, a prediction model for the maximum and minimum horizontal principal stress is constructed to predict the maximum and minimum horizontal principal stress of horizontal wells. Based on the constructed anisotropic fracture pressure prediction model, the fracture pressure prediction of horizontal wells is realized. A collapse pressure prediction model based on the Mohr-Coulomb criterion is used to predict the collapse pressure of horizontal wells.

2. The method according to claim 1, characterized in that, The theoretical rock physics model for shale oil and gas, constructed based on the geological and rock physics characteristics of shale oil and gas, includes: Based on the geological characteristics of unconventional shale oil and gas, a theoretical rock physics model is constructed step by step. The overall technical process is as follows: The equivalent modulus and pore fluid modulus of different types of rocks and minerals were calculated based on the Vogit-Reuss-Hill average theory. Calculate the mixing bulk modulus of different types of fluids based on Wood's formula; Based on the differential equivalent medium model, pores are implanted into the matrix minerals to calculate the bulk modulus and shear modulus of the dry rock skeleton. The elastic matrix of the VTI interlayered background medium is constructed based on Backus average theory; Based on Schoenberg's linear slip theory, high-angle cracks were implanted; By incorporating fluids using the Brown-Korringna anisotropic fluid substitution theory, the bulk modulus and shear modulus of saturated rocks were calculated. Based on the assumptions of Thomsen's weak anisotropy theory, the rock elastic parameters, Thomsen weak anisotropy parameters, and elastic stiffness matrix are obtained.

3. The method according to claim 2, characterized in that, The method combines elemental logging and conventional logging data from horizontal wells, and based on the improved CPS model, corrected overlying formation pressure, and hydrostatic pressure, to achieve formation pressure prediction in horizontal wells, including: By comprehensively utilizing the density logging curves of horizontal wells and pilot wells, and based on the calculation formulas for overburden pressure and hydrostatic pressure, the overburden pressure Pov and hydrostatic pressure Ph corresponding to the horizontal well are calculated. The calculation formulas for overburden pressure and hydrostatic pressure are as follows: In the formula: Pov and Ph represent the overlying formation pressure and hydrostatic pressure, respectively, ρ(z) and ρ w (z) represents the rock density and liquid density under different depth conditions, respectively, g represents the gravitational acceleration, and z represents the depth; Using elemental logging data from horizontal wells and an improved CPS model, the sonic transit time under normal compaction trends in horizontal wells was calculated. Combining the obtained overlying formation pressure, hydrostatic pressure, sonic transit time under normal compaction trend, and actual measured sonic transit time, the predicted formation pressure value for the horizontal well is calculated based on the Eaton formula, which is: P p =P ov -(P ov -P h )(Δt n / Δt) n In the formula: Pp, Pov, and Ph represent formation pressure, overlying formation pressure, and hydrostatic pressure, respectively, and Δt n Δt represents the acoustic transit time under normal compaction conditions, while Δt represents the actual measured acoustic transit time.

4. The method according to claim 3, characterized in that, The elemental logging data of the horizontal well includes: clay minerals, silica minerals, ash minerals, organic matter content, porosity, and water saturation. The calculation of sonic transit time under normal compaction trend in horizontal wells, using elemental logging data from horizontal wells and an improved CPS model, includes: Calculate the stiffness matrix of a mixture of pore fluid and clay particles in "wet clay". Calculate the stiffness matrix of a sandy mixture composed of hard minerals such as siliceous minerals and argillaceous minerals; The stiffness matrix of the equivalent medium composed of the three phases of wet clay-sand mixture-organic matter is obtained based on the Backus average formula. The stiffness matrix of the equivalent shale is converted into the acoustic transit time under normal compaction trend; The expression for the elastic stiffness matrix of the equivalent shale is: C 12 =C 11 -<c 11 >+<c 12 >, C 66 =<c 66 >; In the formula: C ij Let i represent the elastic stiffness components of the equivalent shale, i = 1, 3, 4, 6, j = 1, 2, 3, 4, 6, c ij For each phase, the elastic stiffness component is represented by angle brackets <·>, which indicate a volume-weighted average of the properties within the phase.

5. The method according to claim 4, characterized in that, Based on the assumptions of HTI anisotropic media theory, a prediction model for the maximum and minimum horizontal principal stresses is constructed to predict the maximum and minimum horizontal principal stresses of horizontal wells, including: Obtain formation pressure and overlying formation pressure calculated based on horizontal wells; Based on the conversion relationship between elastic parameters and rock mechanics parameters, the Young's modulus and Poisson's ratio of the horizontal well are calculated. Based on the Schoenberg linear slip theory with the HTI medium assumption, the crack normal compliance and crack tangential compliance were calculated. Tectonic strain coefficients were obtained based on rock physics experimental measurements. Based on the calculated overlying formation pressure, formation pressure, Young's modulus, Poisson's ratio, fracture normal compliance, fracture tangential compliance, and structural strain coefficient, the predicted values ​​of the maximum and minimum horizontal principal stresses of the horizontal well are obtained using the following formulas: In the formula: S h For the minimum horizontal principal stress, S H For the maximum horizontal principal stress, S V For the overlying formation pressure, P p Let E be the formation pressure, E be Young's modulus, σ be Poisson's ratio, and Z be... n Z represents the normal compliance of the crack. t For the tangential compliance of the crack, ε H To construct the strain coefficient.

6. The method according to claim 5, characterized in that, The constructed anisotropic fracture pressure prediction model enables fracture pressure prediction in horizontal wells, including: Tectonic stress coefficients were obtained based on rock physics experimental measurements. The tensile strength was calculated based on the statistical relationship of rock physics in shale oil and gas fields. Obtain formation pressure and overlying formation pressure calculated based on horizontal wells; Obtain the elastic stiffness matrix elements of the equivalent shale obtained from rock physics modeling of shale oil and gas reservoirs; Based on the structural stress coefficient, tensile strength, formation pressure, and overlying formation pressure, the predicted fracture pressure of horizontal wells is calculated using an anisotropic fracture pressure prediction model. The expression for the anisotropic fracture pressure prediction model is as follows: In the formula: P f Rupture pressure, P p Where is the formation pressure, k is the tectonic stress coefficient, S is the overlying formation pressure, and P is the overlying formation pressure. P For formation pressure, S t For tensile strength, C 13 and C 33 These are the stiffness matrix elements of the equivalent shale.

7. The method according to claim 6, characterized in that, The collapse pressure prediction model based on the Mohr-Coulomb criterion enables the prediction of collapse pressure in horizontal wells, including: Based on empirical relationships of rock physics in shale oil and gas reservoirs, cohesion and internal friction angle are calculated. Obtain the maximum and minimum horizontal principal stresses calculated based on horizontal wells; Based on cohesion, internal friction angle, maximum horizontal principal stress, and minimum horizontal principal stress, a collapse pressure prediction model constructed using the Mohr-Coulomb criterion is used to calculate the predicted collapse pressure value of a horizontal well. The expression for the collapse pressure prediction model is as follows: K = cot(π / 4 - φ / 2) In the formula: P m Collapse pressure, S h For the minimum horizontal principal stress, S H φ is the maximum horizontal principal stress, C is the cohesion, and φ is the internal friction angle.

8. An electronic device, characterized in that, The electronic device includes: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, which enables the at least one processor to perform the method for predicting five key engineering parameters of horizontal wells for shale oil and gas reservoirs as described in any one of claims 1-7.

9. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium stores computer instructions for causing a computer to execute the method for predicting five key engineering parameters of horizontal wells for shale oil and gas reservoirs as described in any one of claims 1-7.

10. A device for predicting five key engineering parameters of horizontal wells in shale oil and gas reservoirs, characterized in that, include: The rock physics model building module is used to construct a theoretical rock physics model of shale oil and gas based on the geological and rock physics characteristics of shale oil and gas, and to obtain the elastic parameters, anisotropic parameters and stiffness matrix of the rock. The five key engineering parameter prediction module is used to predict five key engineering parameters of horizontal wells based on the aforementioned shale oil and gas theoretical rock physics model and combined with the geomechanical model. Specifically, these include: The formation pressure prediction submodule is used to combine elemental logging and conventional logging data from horizontal wells, and based on the improved CPS model, corrected overlying formation pressure and hydrostatic pressure, to predict the formation pressure of horizontal wells. The horizontal principal stress prediction submodule is used to construct the maximum and minimum horizontal principal stress prediction models based on the HTI anisotropic medium theory assumptions, so as to realize the prediction of the maximum and minimum horizontal principal stress of horizontal wells. The fracture pressure prediction submodule is used to predict the fracture pressure of horizontal wells based on the constructed anisotropic fracture pressure prediction model. The collapse pressure prediction submodule is used to build a collapse pressure prediction model based on the Mohr-Coulomb criterion to predict the collapse pressure of horizontal wells.

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