Method, device and medium for calculating fracture porosity from dipole shear wave anisotropy

Abstract

The present application relates to a kind of dipole shear wave anisotropy computing fracture porosity method, device and medium, comprising: based on the fast, slow shear wave interval travel time generated by dipole shear wave propagation in fractured formation, the shear wave anisotropy of formation is calculated;Using deep, shallow lateral resistivity, the fracture porosity of formation is calculated;Based on electrical imaging logging, effective structural fracture on well wall formation is picked up, and fracture dip angle is obtained;Select the typical well with better quality of dual lateral resistivity logging curve, fracture porosity and shear wave anisotropy are cross plotted;Based on fracture dip angle, the model for calculating fracture porosity under low and high dip angle conditions is established respectively.The present application provides a new method for quantitative logging evaluation of fracture development intensity in buried hill formation, which can make up for the deficiency that it is difficult to accurately calculate fracture porosity under the condition of distortion of dual lateral resistivity logging curve.

Description

Technical Field

[0001] This invention relates to a method, apparatus, equipment, and medium for calculating fracture porosity using dipole transverse wave anisotropy, and pertains to the field of oil and gas exploration technology. Background Technology

[0002] Buried hill oil and gas reservoirs typically consist of two parts: matrix porosity and fractures. Fractures serve as important channels for oil and gas migration, making it easier for stored oil and gas to migrate into the wellbore. Therefore, the ratio of oil and gas reserves in fractures to total oil and gas reserves (i.e., the fracture-to-reservoir ratio) is a crucial parameter for evaluating recovery rates during the development and assessment of buried hill oil and gas reservoirs. To assess the oil and gas reserves in fractures, accurate calculation of fracture porosity is essential. Currently, the main methods for obtaining fracture porosity in buried hill formations include electrical imaging logging and dual lateral resistivity logging.

[0003] Electro-imaging logging (EML) uses electrodes attached to the wellbore to transmit and receive electrical signals into the formation, providing a 360° panoramic image. This allows for the quantitative characterization of fracture morphology and distribution within the formation, and the calculation of fracture porosity. However, EML calculations of fracture porosity are susceptible to significant errors due to two main factors: firstly, the shallow lateral resistivity is not accurately calibrated from the raw EML data; and secondly, improper selection of instrument parameters in the fracture porosity calculation model. Furthermore, EML calculations only reflect the development intensity of fractures within 5 cm of the wellbore, limiting their accuracy in assessing fracture-related hydrocarbon reserves.

[0004] During drilling, drilling mud infiltrates the formation along fractures, causing a positive differentiation between deep and shallow lateral resistivity logging curves. The degree of differentiation reflects the intensity of fracture development. Considering the influence of fracture orientation on dual lateral resistivity logging, a fracture distortion coefficient is introduced, and simultaneously, the mud resistivity is taken into account, allowing the calculation of formation fracture porosity using both deep and shallow lateral resistivity. However, dual lateral resistivity logging is susceptible to distortion caused by wellbore enlargement and mud loss, making accurate calculation of fracture porosity difficult. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, in response to the above-mentioned problems, the object of the present invention is to provide a method, apparatus, device, and medium for calculating crack porosity using dipole shear wave anisotropy.

[0006] To achieve the above-mentioned objectives, the technical solution provided by this invention is as follows:

[0007] In a first aspect, the present invention provides a method for calculating crack porosity based on dipole transverse wave anisotropy, comprising:

[0008] Shear wave anisotropy of the formation is calculated based on the fast and slow shear wave time differences generated by the propagation of dipole shear waves in fractured formations.

[0009] Calculate formation fracture porosity using deep and shallow lateral resistivity;

[0010] Based on electrical imaging logging, effective structural fractures on the formation of the wellbore are picked up, and the fracture dip angle is obtained;

[0011] Select typical wells with good quality dual lateral resistivity logging curves and interpolate fracture porosity and shear wave anisotropy.

[0012] Based on the crack dip angle, models for calculating crack porosity under shear wave anisotropy under low and high dip angle conditions are established respectively.

[0013] Furthermore, the shear wave anisotropy of the formation is calculated based on the fast and slow shear wave time differences generated by the propagation of dipole shear waves in fractured strata, including:

[0014] Alford coordinate transformation was performed on the orthogonal dipole shear wave logging data to obtain fast shear waves polarized along the fracture direction and slow shear waves polarized perpendicular to the fracture direction.

[0015] The time difference Δt of the fast shear wave was extracted using the slowness-time correlation algorithm. f The time difference Δt between the slow transverse wave and the slow transverse wave s ;

[0016] The shear wave anisotropy of the formation was calculated as follows:

[0017] ANI=2·(Δt s -Δt f ) / (Δt s +Δt f 100%

[0018] In the formula, ANI represents transverse wave anisotropy.

[0019] Furthermore, the orthogonal dipole shear wave logging data includes four components: XX, XY, YX, and YY. X and Y represent the sound source and receiver with polarization directions of 0° and 90° in the horizontal plane, respectively. XX represents the dipole shear wave logging data emitted by the sound source in the X direction and received by the receiver in the X direction; XY represents the dipole shear wave logging data emitted by the sound source in the X direction and received by the receiver in the Y direction; YX represents the dipole shear wave logging data emitted by the sound source in the Y direction and received by the receiver in the X direction; and YY represents the dipole shear wave logging data emitted by the sound source in the Y direction and received by the receiver in the Y direction.

[0020] Furthermore, the formula for calculating the fracture porosity of a formation using deep and shallow lateral resistivity is as follows:

[0021]

[0022] In the formula, Indicates crack porosity, m f C represents the crack porosity index. lls and C lld K represents the shallow and deep lateral conductivity, respectively. f R represents the crack distortion coefficient. mf This indicates the resistivity of the mud.

[0023] Furthermore, based on electrical imaging logging, effective structural fractures on the wellbore formation are picked up, and fracture dip angles are obtained, including:

[0024] Based on dynamic and static images from electrical imaging logging, effective structural fractures with relatively high electrical conductivity distributed on the formation of the wellbore are picked up, and the dip angle of the fractures is obtained. Among them, the effective fractures picked up in the dynamic and static images of electrical imaging logging are structural fractures that cut across the wellbore. Effective fractures are divided into two categories: low dip angle and high dip angle. Low dip angle is a dip angle less than 50°, and high dip angle is a dip angle greater than or equal to 50°.

[0025] Furthermore, the model for calculating crack porosity under low tilt angle conditions with transverse wave anisotropy is as follows:

[0026] Φ f =0.091·ANI

[0027] In the formula, Φ f It represents crack porosity; ANI represents transverse wave anisotropy.

[0028] Furthermore, the model for calculating crack porosity under high tilt angle conditions with transverse wave anisotropy is as follows:

[0029] Φ f =0.082·ANI

[0030] In the formula, Φ f It represents crack porosity; ANI represents transverse wave anisotropy.

[0031] Secondly, the present invention also provides an apparatus for calculating crack porosity based on dipole transverse wave anisotropy, the apparatus comprising:

[0032] The shear wave anisotropy calculation unit is configured to calculate the shear wave anisotropy of the formation based on the fast and slow shear wave time difference generated by the propagation of dipole shear waves in fractured formations.

[0033] The fracture porosity calculation unit is configured to calculate the fracture porosity of the formation using deep and shallow lateral resistivity;

[0034] The fracture dip angle calculation unit is configured to pick up effective structural fractures on the wellbore formation based on electrical imaging logging and obtain the fracture dip angle;

[0035] The intersection unit is configured to select typical wells with good quality dual lateral resistivity logging curves and intersect fracture porosity and shear wave anisotropy.

[0036] The model building unit is configured to build models for calculating crack porosity based on crack dip angle under low and high dip angle conditions, respectively, using shear wave anisotropy.

[0037] Thirdly, the present invention also provides an electronic device comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs include instructions for performing any of the methods.

[0038] Fourthly, the present invention also provides a computer-readable storage medium for storing one or more programs, characterized in that the one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any of the methods.

[0039] Because the present invention adopts the above technical solution, it has the following characteristics:

[0040] 1. This invention selects typical wells with good quality dual-lateral resistivity logging curves in the target area to ensure the accuracy and reliability of fracture porosity calculated from deep and shallow lateral resistivity. Then, it performs cross-fitting with the shear wave anisotropy calculated from the fast and slow shear wave time differences in typical wells to eliminate the influence of fracture dip angle. Models for calculating fracture porosity based on shear wave anisotropy under low and high dip angle conditions are established respectively. Therefore, it can accurately evaluate the development intensity of fractures within 1m of the well. This not only compensates for the inaccuracy in calculating fracture porosity under distorted dual-lateral resistivity logging curves but also overcomes the limitations of electrical imaging logging in evaluating oil and gas reserves in fractures. It can accurately calculate fracture porosity and is a simple, practical, and widely applicable new method.

[0041] 2. The orthogonal dipole shear wave logging of the present invention is less affected by wellbore enlargement and mud loss, and the logging data quality is higher, which can provide more reliable basic data for fracture porosity calculation.

[0042] In summary, this invention can be widely applied to crack porosity calculation. Attached Figure Description

[0043] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings:

[0044] Figure 1 This is a flowchart of a method for calculating crack porosity based on dipole transverse wave anisotropy according to an embodiment of the present invention.

[0045] Figure 2 Figure (a) shows a schematic diagram and waveform diagram of fast and slow shear wave propagation in a fractured formation according to an embodiment of the present invention, and Figure (b) shows a schematic diagram of fast and slow shear wave waveforms.

[0046] Figure 3 This invention relates to an embodiment of the invention, which calculates crack porosity based on deep and shallow lateral resistivity and transverse wave anisotropy based on fast and slow transverse wave time differences.

[0047] Figure 4 This invention relates to an embodiment of an electrical imaging logging image that captures effective fractures with high electrical conductivity and fracture dip angles.

[0048] Figure 5 Figure 1 shows the cross-fitting results of calculating crack porosity under shear wave anisotropy under low and high dip angle conditions according to an embodiment of the present invention. Figure 2 shows the crack porosity model calculated by shear wave anisotropy under low dip angle, and Figure 3 shows the crack porosity model calculated by shear wave anisotropy under high dip angle.

[0049] Figure 6 This is a schematic diagram showing the comparison between crack porosity calculated by transverse wave anisotropy and crack porosity calculated by deep and shallow lateral resistivity, according to an embodiment of the present invention.

[0050] Figure 7 This is a structural diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0051] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0052] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0053] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.

[0054] Because existing methods for calculating fracture porosity in buried hill reservoirs are inaccurate, this invention aims to compensate for the difficulty in accurately calculating fracture porosity under distorted dual-lateral resistivity logging curves. The invention provides a method, apparatus, equipment, and medium for calculating fracture porosity using dipole shear wave anisotropy, comprising: calculating the formation's shear wave anisotropy based on the fast and slow shear wave time differences; calculating the formation's fracture porosity using deep and shallow lateral resistivity, considering mud resistivity and fracture distortion coefficients; acquiring effective structural fractures on the wellbore based on electrical imaging logging and obtaining the fracture dip angle; selecting typical wells with good dual-lateral resistivity logging curve quality and intersecting the fracture porosity calculated from deep and shallow lateral resistivity in the gas layer with the shear wave anisotropy; and establishing models for calculating fracture porosity under low and high dip angle conditions based on the dip angle of fractures obtained from electrical imaging logging. Therefore, this invention provides a new method for quantitative well logging evaluation of fracture development intensity in buried hill formations, which can make up for the inability to accurately calculate fracture porosity when the dual lateral resistivity logging curves are distorted.

[0055] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0056] Example 1: As Figure 1As shown in this embodiment, the method for calculating crack porosity based on dipole shear wave anisotropy includes:

[0057] S1. Dipole shear waves propagate in fractured formations, generating fast and slow shear waves. The shear wave anisotropy of the formation is calculated based on the time difference between the fast and slow shear waves.

[0058] In this embodiment, the fractured formation exhibits circumferential anisotropy (HTI) characteristics. When dipole shear waves propagate in the fractured formation, fast and slow shear wave splitting occurs. The fast shear wave is polarized along the fracture direction, while the slow shear wave is polarized perpendicular to the fracture direction. The velocity difference between the two reflects the formation shear wave anisotropy caused by the fracture. The time difference between the fast and slow shear waves is positively correlated with the fracture porosity.

[0059] In this embodiment, the specific process of calculating the shear wave anisotropy of the formation based on the fast and slow shear wave time differences includes:

[0060] like Figure 2 As shown, the orthogonal dipole shear wave logging data includes four components: XX, XY, YX, and YY. X and Y represent the source and receiver with polarization directions of 0° and 90° in the horizontal plane, respectively. XX represents the dipole shear wave logging data emitted by the source in the X direction and received by the receiver in the X direction; XY represents the dipole shear wave logging data emitted by the source in the X direction and received by the receiver in the Y direction; YX represents the dipole shear wave logging data emitted by the source in the Y direction and received by the receiver in the X direction; and YY represents the dipole shear wave logging data emitted by the source in the Y direction and received by the receiver in the Y direction. The four-component orthogonal dipole shear wave logging data are subjected to Alford coordinate transformation to obtain fast shear waves polarized along the fracture strike and slow shear waves polarized perpendicular to the fracture strike. The time difference Δt of the fast shear wave is extracted using the slowness-time correlation algorithm. f The time difference Δt between the slow transverse wave and the slow transverse wave s The shear wave anisotropy of the strata can be calculated from these two factors:

[0061] ANI=2·(Δt s -Δt f ) / (Δt s +Δt f 100% (1)

[0062] In the formula, ANI represents the transverse wave anisotropy, expressed as a percentage (%); Δt f and Δt s The unit is us / ft.

[0063] S2. Considering mud resistivity and fracture distortion coefficient, calculate formation fracture porosity using deep and shallow lateral resistivity.

[0064] In this embodiment, the influence of fracture orientation on dual lateral resistivity logging is considered, and a fracture distortion coefficient is introduced. At the same time, the resistivity of the drilling mud is considered, and the fracture porosity of the formation is calculated using deep and shallow lateral resistivity.

[0065] Furthermore, the formula for calculating crack porosity using deep and shallow lateral resistivity is as follows:

[0066]

[0067] In the formula, R represents crack porosity, expressed in v / v. mf Resistivity of mud filtrate is expressed in Ω·m; m f Indicates the crack porosity index; C lls and C lld These represent the shallow and deep lateral conductivity, respectively, in units of S / m.

[0068] Considering the actual conditions of the target gas field, the above formula was modified in two aspects: First, the intrusion in the fracture is mud, not mud filtrate, so R in the formula was changed. mf Change to R m Secondly, considering the influence of fracture orientation on deep and shallow lateral resistivity, a fracture distortion coefficient K is introduced. f Therefore, formula (2) is modified as follows:

[0069]

[0070] Based on experimental research results, the fracture porosity index used when calculating fracture porosity using this formula can be m. f =1.5, considering that the target area is dominated by medium to high dip angle cracks, the crack distortion coefficient can be K. f =1.1. Experimental studies show that for horizontal cracks, the crack distortion coefficient is taken as 1.3, and for vertical cracks, the crack distortion coefficient is taken as 1.0. This is just one example, and it is not limited to these values. The appropriate value can be selected according to actual needs.

[0071] S3. Based on electrical imaging logging, effective structural fractures on the wellbore formation are picked up, and the dip angle of the fractures is obtained.

[0072] In this embodiment, based on the dynamic and static images of electrical imaging logging, effective structural fractures with relatively high electrical conductivity distributed on the formation of the wellbore are picked out, and the dip angle of the fractures is obtained.

[0073] Furthermore, the effective fractures picked up in the dynamic and static images of electrical imaging logging are structural fractures that cut across the wellbore, rather than induced fractures generated during drilling due to stress release that extend vertically along the formation and are symmetrically distributed at 180°. Effective fractures are divided into two categories: low dip angle and high dip angle. When the dip angle is <50°, it is defined as low dip angle; when the dip angle is >50°, it is defined as high dip angle.

[0074] Taking Well A, whose deep and shallow lateral resistivity logging curves in the gas field target area are of good quality, as an example, the shear wave anisotropy of the formation was calculated using formula (1) in step S1 and the fracture porosity of the formation was calculated using formula (3) in step S2. The variation trends of the two along the well direction are well consistent, indicating that the shear wave anisotropy of the formation can effectively reflect the fracture porosity, such as Figure 3 As shown.

[0075] S4. Select typical wells with good quality dual lateral resistivity logging curves and intersect the fracture porosity calculated from the deep and shallow lateral resistivity in the gas layer by logging interpretation with shear wave anisotropy.

[0076] In this embodiment, a typical well with good quality dual lateral resistivity logging curves in the gas field target area is preferred. The fracture porosity calculated from the deep and shallow lateral resistivity in the gas layer is cross-fitted with the shear wave anisotropy to eliminate the influence of fracture dip angle. The typical well is an exploration well with good quality dual lateral resistivity logging curves, such as... Figure 3 The RD and RS trends shown in the third curve are consistent, without any abrupt curve distortion, ensuring the reliability of crack porosity calculations for both deep and shallow resistivity.

[0077] The magnitude of formation shear wave anisotropy is influenced not only by fracture development intensity but also by fracture dip angle. To improve the accuracy of fracture porosity calculation based on shear wave anisotropy, the influence of fracture dip angle needs to be eliminated. Therefore, based on dynamic and static images from electrical imaging logging, effective structural fractures with high electrical conductivity distributed on the formation along the wellbore are identified, and their dip angles are obtained. Figure 4 As shown.

[0078] S5. Based on the dip angle of fractures in the gas reservoir obtained by electrical imaging logging, models for calculating fracture porosity under low and high dip angle conditions with shear wave anisotropy are established respectively.

[0079] In this embodiment, dual-lateral resistivity logging is easily affected by wellbore enlargement and mud loss, leading to curve distortion. In contrast, orthogonal dipole shear wave logging is less affected and provides higher quality logging data. For the case of curve distortion in dual-lateral resistivity logging, the fracture porosity calculated using dipole shear wave anisotropy is more accurate and reliable.

[0080] Furthermore, six representative wells with good quality deep and shallow lateral resistivity logging curves from the gas field target area were selected. The fracture porosity calculated from the deep and shallow lateral resistivity in the gas layer was intersected with the shear wave anisotropy. Based on the fracture dip angle obtained from electrical imaging logging, a formula model for calculating fracture porosity using shear wave anisotropy under fracture dip angles less than 50° was established as follows:

[0081] Φ f =0.091·ANI (4)

[0082] In the formula, Φ f The value represents crack porosity, expressed as a percentage (%); ANI represents transverse wave anisotropy, expressed as a percentage (%).

[0083] The formula for calculating crack porosity under transverse wave anisotropy when the crack dip angle is greater than or equal to 50° is:

[0084] Φ f =0.082·ANI (5)

[0085] Among them, the cross-fit results of the crack porosity calculation for transverse wave anisotropy under low and high tilt angle conditions are as follows: Figure 5 As shown.

[0086] For typical well sections with good quality deep and shallow lateral resistivity logging curves, the fracture porosity calculated using the combination of formulas (4) and (5) described in step S5, based on the fracture dip angle obtained from electrical imaging logging, is similar to the fracture porosity calculated using dual lateral resistivity, with a relative error of only 8.3%. Figure 6 As shown in (a); for well sections where the deep and shallow lateral resistivity logging curves are distorted, the fracture porosity calculated using the combination of formulas (4) and (5) described in step S5 is 48% more accurate than the fracture porosity calculated using dual lateral resistivity, such as Figure 6 As shown in (b).

[0087] In summary, this invention provides a new method for quantitative well logging evaluation of fracture development intensity in buried hill formations, overcoming the inability to accurately calculate fracture porosity when dual lateral resistivity logging curves are distorted.

[0088] Example 2: Following the method for calculating crack porosity using dipole shear wave anisotropy provided in Example 1, this example provides an apparatus for calculating crack porosity using dipole shear wave anisotropy. The apparatus provided in this example can implement the method for calculating crack porosity using dipole shear wave anisotropy in Example 1. This apparatus can be implemented through software, hardware, or a combination of both. For ease of description, this example is described by dividing the functionality into various units. Of course, in implementation, the functions of each unit can be implemented in one or more software and / or hardware components. For example, the apparatus may include integrated or separate functional modules or units to perform the corresponding steps in the methods of Example 1. Since the apparatus in this example is basically similar to the method example, the description process of this example is relatively simple. Relevant details can be found in the description of Example 1. The embodiment of the apparatus for calculating crack porosity using dipole shear wave anisotropy provided by this invention is merely illustrative.

[0089] Specifically, this embodiment provides an apparatus for calculating crack porosity based on dipole transverse wave anisotropy, the apparatus comprising:

[0090] The shear wave anisotropy calculation unit is configured to calculate the shear wave anisotropy of the formation based on the fast and slow shear wave time difference generated by the propagation of dipole shear waves in fractured formations.

[0091] The fracture porosity calculation unit is configured to calculate the fracture porosity of the formation using deep and shallow lateral resistivity;

[0092] The fracture dip angle calculation unit is configured to pick up effective structural fractures on the wellbore formation based on electrical imaging logging and obtain the fracture dip angle;

[0093] The intersection unit is configured to select typical wells with good quality dual lateral resistivity logging curves and intersect fracture porosity and shear wave anisotropy.

[0094] The model building unit is configured to build models for calculating crack porosity based on crack dip angle under low and high dip angle conditions, respectively, using shear wave anisotropy.

[0095] Example 3: This example provides an electronic device corresponding to the method for calculating crack porosity based on dipole transverse wave anisotropy provided in Example 1. The electronic device can be a client-side electronic device, such as a mobile phone, laptop, tablet, or desktop computer, to execute the method of Example 1.

[0096] like Figure 7As shown, the electronic device includes a processor, memory, communication interface, and bus. The processor, memory, and communication interface are connected via the bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Component (EISA) bus, etc. The memory stores a computer program that can run on the processor. When the processor runs the computer program, it executes the method of Embodiment 1. The implementation principle and technical effects are similar to those of Embodiment 1, and will not be repeated here. Those skilled in the art will understand that... Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computing device on which the present application is applied. The specific computing device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0097] In a preferred embodiment, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), and optical discs.

[0098] In a preferred embodiment, the processor can be any type of general-purpose processor such as a central processing unit (CPU) or a digital signal processor (DSP), and is not limited thereto.

[0099] Example 4: This example provides a computer program product. The computer program product may include a computer program stored on a computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by the computer, the computer can execute the method provided in Example 1 above. Its implementation principle and technical effects are similar to those in Example 1, and will not be repeated here.

[0100] In a preferred embodiment, the computer-readable storage medium may be a tangible device for holding and storing instructions used by an instruction execution device, such as, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof. The computer-readable storage medium stores computer program instructions that cause a computer to perform the method provided in Embodiment 1 above.

[0101] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "a preferred embodiment," "furthermore," "specifically," "in this embodiment," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0102] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (devices), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0103] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating crack porosity based on dipole transverse wave anisotropy, characterized in that, include: Shear wave anisotropy of the formation is calculated based on the fast and slow shear wave time differences generated by the propagation of dipole shear waves in fractured formations. Calculate formation fracture porosity using deep and shallow lateral resistivity; Based on electrical imaging logging, effective structural fractures on the formation of the wellbore are picked up, and the fracture dip angle is obtained; Select typical wells with good quality dual lateral resistivity logging curves, and intersect the calculation of formation shear wave anisotropy based on the fast and slow shear wave time difference generated by the propagation of dipole shear waves in fractured formations and the calculation of formation fracture porosity using deep and shallow lateral resistivity. Based on the crack dip angle, models for calculating crack porosity under shear wave anisotropy under low and high dip angle conditions are established respectively, wherein: The model for calculating crack porosity under low tilt angle conditions with transverse wave anisotropy is as follows: Φ f =0.091· ANI ； The model for calculating crack porosity under high tilt angle conditions with transverse wave anisotropy is as follows: Φ f =0.082· ANI ； In the formula, Φ f Indicates crack porosity; ANI It is anisotropic for transverse waves.

2. The method for calculating crack porosity based on dipole transverse wave anisotropy according to claim 1, characterized in that, The shear wave anisotropy of the formation is calculated based on the fast and slow shear wave time differences generated by dipole shear waves propagating in fractured strata, including: Alford coordinate transformation was performed on the orthogonal dipole shear wave logging data to obtain fast shear waves polarized along the fracture direction and slow shear waves polarized perpendicular to the fracture direction. The time difference of fast shear waves was extracted using a slowness-time correlation algorithm. Δt f Time difference with slow transverse waves Δt s ; The shear wave anisotropy of the formation was calculated as follows: ANI =2·( Δt s - Δt f ) / ( Δt s + Δt f )·100%； In the formula, ANI It is anisotropic for transverse waves.

3. The method for calculating crack porosity based on dipole transverse wave anisotropy according to claim 2, characterized in that, Orthogonal dipole shear wave logging data includes XX , XY , YX and YY Four components ，X and Y These represent a sound source and a receiver positioned at 0° and 90° in the horizontal plane, respectively. XX express X Directional sound source emission, X Dipole shear wave logging data received by the directional receiver; XY express X Directional sound source emission, Y Dipole shear wave logging data received by the directional receiver; YX express Y Directional sound source emission, X Dipole shear wave logging data received by the directional receiver; YY express Y Directional sound source emission, Y Dipole shear wave logging data received by the directional receiver.

4. The method for calculating crack porosity based on dipole transverse wave anisotropy according to claim 1, characterized in that, The formula for calculating formation fracture porosity using deep and shallow lateral resistivity is as follows: ； In the formula, Indicates crack porosity. m f Indicates the crack porosity index. C lls and C lld These represent the shallow and deep lateral conductivity, respectively. K f Indicates the crack distortion coefficient. R m This indicates the resistivity of the mud.

5. The method for calculating crack porosity based on dipole transverse wave anisotropy according to claim 1, characterized in that, Based on electrical imaging logging, effective structural fractures on the wellbore are picked up, and fracture dip angles are obtained, including: Based on dynamic and static images from electrical imaging logging, effective structural fractures with relatively high electrical conductivity distributed on the formation of the wellbore are picked up, and the dip angle of the fractures is obtained. Among them, the effective fractures picked up in the dynamic and static images of electrical imaging logging are structural fractures that cut across the wellbore. Effective fractures are divided into two categories: low dip angle and high dip angle. Low dip angle is a dip angle less than 50°, and high dip angle is a dip angle greater than or equal to 50°.

6. An apparatus for calculating crack porosity using dipole shear wave anisotropy, used to implement the method for calculating crack porosity using dipole shear wave anisotropy as described in any one of claims 1 to 5, characterized in that, The device includes: The shear wave anisotropy calculation unit is configured to calculate the shear wave anisotropy of the formation based on the fast and slow shear wave time difference generated by the propagation of dipole shear waves in fractured formations. The fracture porosity calculation unit is configured to calculate the fracture porosity of the formation using deep and shallow lateral resistivity; The fracture dip angle calculation unit is configured to pick up effective structural fractures on the wellbore formation based on electrical imaging logging and obtain the fracture dip angle; The intersection unit is configured to select typical wells with good quality dual lateral resistivity logging curves, and to intersect the formation's shear wave anisotropy calculated based on the fast and slow shear wave time difference generated by the propagation of dipole shear waves in fractured formations, and to calculate the formation's fracture porosity using deep and shallow lateral resistivity. The model building unit is configured to build models for calculating crack porosity based on crack dip angle under low and high dip angle conditions, respectively, using shear wave anisotropy.

7. An electronic device, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for performing any of the methods described in claims 1 to 5.

8. A computer-readable storage medium for storing one or more programs, characterized in that, The one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any of the methods described in claims 1 to 5.

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