Fractured formation porosity determination method and device and computer equipment

Abstract

The invention relates to the technical field of complex reservoir exploration and development, in particular to a method for determining the porosity of a fractured formation, and a device for determining the porosity of the fractured formation obtains numerical simulation parameters through a fractured formation model pre-established by the device for determining the porosity of the fractured formation. Applying a three-dimensional finite difference method to perform interval transit time logging response numerical simulation on a pre-established fractured formation model to obtain interval transit time porosity; and performing neutron logging response numerical simulation on a pre-established fractured formation model by applying a Monte Carlo method to obtain the neutron porosity. The interval transit time porosity obtained through numerical simulation is compared with the neutron porosity, and the maximum value is used as the fractured formation porosity. According to the method, the three-dimensional finite difference method and the Monte Carlo method are adopted for numerical simulation through the fractured formation model, so that the accurate fractured formation porosity determination method is provided, and reliable parameters are provided for explanation and evaluation of the fractured formation.

Description

Technical Field

[0001] The present application relates to the technical field of complex reservoir exploration and development, and in particular to a method, device and computer equipment for determining the porosity of fractured formations. Background Art

[0002] Porosity is an important parameter for reservoir interpretation and evaluation, and accurate determination of porosity is an important part of logging processing and interpretation. Some studies have been conducted on porosity determination methods: First, a new effective porosity calculation model was established by recursively analyzing logging data that is less affected by fluid phase. Second, using multivariate statistical methods, SPSS software as a platform, and making full use of core physical property data, a model of the relationship between core porosity and three-porosity logging data was established. Third, based on e~((1-△SP)), AC and CNL were corrected for mud to establish a porosity interpretation model for complex tight reservoirs. Fourth, through sensitivity curve analysis, the content of mineral components can be obtained by establishing a multi-parameter model using natural gamma, sonic time difference, and neutron porosity curves.

[0003] Porosity is based on mineral composition, combined with density curve and volume model to obtain total reservoir porosity and effective porosity. In the past, the porosity determination method was either purely based on theoretical deduction or directly applied the relationship between logging curve and reservoir parameters, without the influence of various factors such as logging curve and porosity based on numerical simulation. Summary of the invention

[0004] Based on this, it is necessary to provide a method, device and computer equipment for determining the porosity of fractured formations in order to solve the above technical problems.

[0005] In a first aspect, the present application provides a method for determining porosity of a fractured formation, comprising:

[0006] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0007] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0008] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0009] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0010] In one embodiment, before the step of applying the three-dimensional finite difference method to the pre-established fracture formation model to perform a numerical simulation of the acoustic transit time logging response to obtain the acoustic transit time porosity, the method includes:

[0011] The fracture formation model established is:

[0012]

[0013] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0014] In one embodiment, a three-dimensional finite difference method is used to perform a numerical simulation of the acoustic transit time logging response on a pre-established fracture formation model to obtain the acoustic transit time porosity, including:

[0015] The acoustic time difference is obtained by numerical simulation;

[0016] application and Obtain the sonic transit time porosity.

[0017] In one embodiment, the Monte Carlo method is used to perform numerical simulation of neutron logging response on a pre-established fracture formation model to obtain neutron porosity, including:

[0018] Neutrons were obtained by numerical simulation;

[0019] application and Get the neutron porosity.

[0020] In one embodiment, the maximum value of the acoustic transit time porosity and the neutron porosity is used as the fracture formation porosity, including:

[0021] Compare neutron porosity and sonic transit time porosity;

[0022] The maximum value is taken as the final fracture formation porosity.

[0023] In one embodiment, comparing neutron porosity and sonic transit time porosity comprises:

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0030] In a second aspect, the present application also provides a device for determining porosity of a fractured formation, comprising:

[0031] An acquisition unit is used to acquire numerical simulation parameters, which include bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0032] The sonic transit time porosity unit is used to numerically simulate the sonic transit time logging response of the pre-established fracture formation model using the three-dimensional finite difference method to obtain the sonic transit time porosity;

[0033] Neutron porosity unit, used to apply Monte Carlo method to the pre-established fracture formation model, to perform numerical simulation of neutron logging response and obtain neutron porosity;

[0034] The fractured formation porosity unit is used to take the maximum value of the sonic time difference porosity and the neutron porosity as the fractured formation porosity.

[0035] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0036] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0037] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0038] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0039] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0040] In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0041] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0042] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0043] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0044] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0045] In a fifth aspect, the present application further provides a computer program. When the computer program is executed by a processor, the following steps are implemented:

[0046] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0047] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0048] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0049] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0050] The above-mentioned method, device, computer equipment and storage medium for determining the porosity of fractured formations obtain numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic time difference, bedrock neutrons, mud acoustic time difference in fractures and mud neutrons in fractures; the three-dimensional finite difference method is used to numerically simulate the acoustic time difference logging response of the pre-established fractured formation model to obtain the acoustic time difference porosity; the Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fractured formation model to obtain the neutron porosity; the maximum value of the acoustic time difference porosity and the neutron porosity is used as the fractured formation porosity. The present application provides an accurate method for determining the porosity of fractured formations, which provides reliable parameters for the interpretation and evaluation of fractured formations. The required logging method is a conventional logging method, which has strong operability and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 A schematic diagram of an application scenario flow of a method for determining porosity of fractured formations in one embodiment;

[0053] Figure 2 A schematic diagram of a sonic time difference porosity flow chart of a method for determining porosity of fractured formations in one embodiment;

[0054] Figure 3 A schematic diagram of a neutron porosity flow chart of a method for determining porosity of fractured formations in one embodiment;

[0055] Figure 4 A schematic diagram of a fractured formation porosity flow chart of a fractured formation porosity determination method in one embodiment;

[0056] Figure 5 A schematic diagram of an application flow of a method for determining porosity of fractured formations in one embodiment;

[0057] Figure 6 It is a schematic diagram of the implementation process of a method for determining the porosity of a fractured formation in one embodiment;

[0058] Figure 7 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0059] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0060] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all couplings of one or more related listed items.

[0061] It can be understood that the terms "first", "second", etc. used in the present application can be used in this article to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element.

[0062] A method for determining the porosity of a fractured formation provided in an embodiment of the present application, first, determines the bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic time difference, bedrock neutron, mud acoustic time difference in the fracture, and mud neutron in the fracture in the fracture model; secondly, determines the porosity in the model; thirdly, applies a three-dimensional finite difference method to simulate the acoustic time difference logging response, applies a Monte Carlo method to simulate the neutron logging response, and establishes a neutron porosity method and an acoustic time difference porosity method based on the numerical simulation results; finally, compares the neutron porosity and the acoustic time difference porosity, and takes the maximum value as the final porosity. The present application can provide accurate fractured formation porosity, and provide reliable parameters for fractured formation interpretation and evaluation. The required logging method is a conventional logging method, which has strong operability and practicality.

[0063] Embodiment 1

[0064] like Figure 1 As shown, in this embodiment, a method for determining the porosity of a fractured formation is provided, comprising the following steps:

[0065] S101: Acquire numerical simulation parameters, which include bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutrons, mud acoustic wave time difference in fractures, and mud neutrons in fractures.

[0066] Specifically, the fracture formation porosity determination device obtains the bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in the fracture and mud neutron in the fracture for numerical simulation. In this embodiment, the fracture in the fracture formation model is a flat plate model. The simulation conditions of the flat plate model are: the bedrock formation porosity is 1%, the fracture widths are 0.1mm, 1mm, 1cm and 1dm respectively, the fracture inclinations are 0 degrees, 30 degrees, 45 degrees, 60 degrees and 90 degrees respectively, the bedrock acoustic wave time difference is 48.9us / ft, the bedrock neutron is 1%, the mud acoustic wave time difference in the fracture is 197us / ft, and the neutron in the fracture is 91%.

[0067] S102: Applying the three-dimensional finite difference method to the pre-established fracture formation model, numerical simulation of the acoustic time difference logging response is performed to obtain the acoustic time difference porosity.

[0068] Specifically, the fracture formation porosity determination device needs to establish a fracture formation model before performing numerical simulation. In this embodiment, the fractures in the fracture formation model are flat plate models. The fracture formation porosity determination device uses a three-dimensional finite difference method to perform a numerical simulation of the acoustic time difference logging response based on the established fracture formation model to obtain the acoustic time difference porosity.

[0069] S103: Applying the Monte Carlo method to the pre-established fracture formation model, numerical simulation of neutron logging response is performed to obtain neutron porosity.

[0070] Specifically, the fracture formation porosity determination device needs to establish a fracture formation model before performing numerical simulation. In this embodiment, the fractures in the fracture formation model are flat plate models. The fracture formation porosity determination device uses the Monte Carlo method to perform numerical simulation of neutron logging response based on the established fracture formation model to obtain neutron porosity.

[0071] S104: Taking the maximum value of the sonic time difference porosity and the neutron porosity as the fracture formation porosity.

[0072] Specifically, the fractured formation porosity determination device compares the acoustic time difference porosity obtained in step S102 and the neutron porosity obtained in step S103, and takes the maximum value thereof as the fractured formation porosity.

[0073] In this embodiment, a method for determining the porosity of a fractured formation is provided. The fractured formation porosity determination device of the method obtains numerical simulation parameters, wherein the numerical simulation parameters include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic time difference, bedrock neutrons, mud acoustic time difference in fractures, and mud neutrons in fractures. The fractured formation porosity determination device pre-establishes a fractured formation model, and applies a three-dimensional finite difference method to perform a numerical simulation of the acoustic time difference logging response on the pre-established fractured formation model to obtain the acoustic time difference porosity; and applies a Monte Carlo method to perform a numerical simulation of the neutron logging response on the pre-established fractured formation model to obtain the neutron porosity. The acoustic time difference porosity and neutron porosity obtained by numerical simulation are compared, and the maximum value thereof is taken as the fractured formation porosity. The present application adopts a fractured formation model, and uses a three-dimensional finite difference method and a Monte Carlo method for numerical simulation, respectively, thereby providing an accurate method for determining the porosity of fractured formations, providing reliable parameters for the interpretation and evaluation of fractured formations, and the required logging method is a conventional logging method, which has strong operability and practicality.

[0074] Embodiment 2

[0075] In this embodiment, step S102 is provided: applying the three-dimensional finite difference method to the pre-established fracture formation model to perform a numerical simulation of the acoustic time difference logging response to obtain the acoustic time difference porosity step, including: establishing a fracture formation model, wherein the fracture formation model is as follows:

[0076]

[0077] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0078] In this embodiment, the fractured formation porosity determination device provides an accurate fractured formation porosity determination method, provides reliable parameters for fractured formation interpretation and evaluation, and the required logging methods are highly operable and practical.

[0079] Embodiment 3

[0080] like Figure 2 As shown, in this embodiment, step S102 is provided: applying a three-dimensional finite difference method to a pre-established fracture formation model to perform a numerical simulation of the acoustic transit time logging response to obtain the acoustic transit time porosity, including:

[0081] S1021: Numerical simulation to obtain the acoustic wave time difference.

[0082] Specifically, the three-dimensional finite difference method is applied to the pre-established fracture formation model to perform numerical simulation of the acoustic time difference logging response to obtain the acoustic time difference.

[0083] S1022: Application and Obtain the sonic transit time porosity.

[0084] Specifically, the fracture formation porosity determination device analyzes the relationship between the simulated acoustic wave time difference and the porosity in the model, and establishes a formula for calculating porosity using the acoustic wave time difference. and like Figure 4 The 5th one in the.

[0085] In this embodiment, the fracture formation porosity determination device analyzes the relationship between the acoustic wave time difference obtained by simulation and the porosity in the model to establish a formula for calculating porosity by acoustic wave time difference, which has strong operability and practicality.

[0086] Embodiment 4:

[0087] like Figure 3 As shown, in this embodiment, step S103 is provided: applying the Monte Carlo method to the pre-established fracture formation model to perform a neutron logging response numerical simulation to obtain the neutron porosity, including:

[0088] S1031: Neutrons obtained by numerical simulation.

[0089] Specifically, the Monte Carlo method is used to perform numerical simulation of neutron logging response on a pre-established fracture formation model to obtain neutrons.

[0090] S1032: Application and Get the neutron porosity.

[0091] Specifically, the fracture formation porosity determination device analyzes the relationship between the simulated neutrons and the porosity in the model, such as Figure 5 The 6th track in the application of the device for determining the porosity of fractured formations and The formula for porosity is as follows: Figure 5 The 7th one in the.

[0092] In this embodiment, the fracture formation porosity determination device analyzes the relationship between the simulated neutrons and the porosity in the model, and the required logging method is a conventional logging method, which has strong operability and practicability.

[0093] Embodiment 5

[0094] like Figure 4 As shown, in this embodiment, step S104 is provided: taking the maximum value of the acoustic time difference porosity and the neutron porosity as the fracture formation porosity, including:

[0095] S1041: Compare neutron porosity and sonic transit time porosity.

[0096] Specifically, the fracture formation porosity determination device compares the obtained neutron porosity and the acoustic wave transit time porosity.

[0097] S1042: Take the maximum value as the final fracture formation porosity.

[0098] Specifically, the fracture formation porosity determination device compares the obtained neutron porosity and acoustic wave transit time porosity. The maximum value is taken as the final fracture formation porosity, such as Figure 5 No. 8 in the list.

[0099] In this embodiment, step S1041 is also provided: comparing the neutron porosity and the sonic transit time porosity, and the specific steps include:

[0100]

[0101]

[0102]

[0103]

[0104]

[0105] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0106] In this embodiment, the fractured formation porosity determination device compares the neutron porosity and the acoustic wave transit time porosity, and takes the maximum value as the final porosity, thereby providing reliable parameters for fractured formation interpretation and evaluation, and further improving the accuracy of fractured formation interpretation.

[0107] Embodiment 6

[0108] like Figure 6As shown, in this embodiment, taking the processing of actual well data in a certain study area in the west as an example, the specific implementation method is as follows. First, the fracture formation porosity determination device extracts the uranium-free gamma in the well data, such as Figure 5 In Question 2, apply the formula The mud content is calculated as Figure 5 The fracture formation porosity determination device extracts neutrons from well data, such as Figure 5 The fourth track in the series. Application of the device for determining the porosity of fractured formations and The neutron porosity is obtained as Figure 5 The fracture formation porosity determination device extracts the acoustic time difference in the well data, such as Figure 5 Track 6 in the figure shows the application formula of fracture formation porosity and formula The sonic transit time porosity is obtained as Figure 5 The 7th channel in the fracture formation porosity is to compare the obtained neutron porosity and sonic time difference porosity, and take the maximum value as the final porosity, such as Figure 5 The 8th one in the.

[0109] In this embodiment, the porosity determined by the fracture formation porosity determination device has a good correlation with the core porosity obtained by core experiments.

[0110] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0111] Based on the same inventive concept, the embodiment of the present application also provides a fractured formation porosity determination device for implementing the fractured formation porosity determination method involved above. The implementation scheme for solving the problem provided by the fractured formation porosity determination device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more fractured formation porosity determination device embodiments provided below can refer to the limitations of the fractured formation porosity determination method above, and will not be repeated here.

[0112] In one embodiment, a device for determining porosity of a fractured formation is provided, comprising:

[0113] An acquisition unit is used to acquire numerical simulation parameters, which include bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0114] The sonic transit time porosity unit is used to numerically simulate the sonic transit time logging response of the pre-established fracture formation model using the three-dimensional finite difference method to obtain the sonic transit time porosity;

[0115] Neutron porosity unit, used to apply Monte Carlo method to the pre-established fracture formation model, to perform numerical simulation of neutron logging response and obtain neutron porosity;

[0116] The fractured formation porosity unit is used to take the maximum value of the sonic time difference porosity and the neutron porosity as the fractured formation porosity.

[0117] In one embodiment, before the step of applying the three-dimensional finite difference method to the pre-established fracture formation model to perform a numerical simulation of the acoustic transit time logging response to obtain the acoustic transit time porosity, the method includes:

[0118] The fracture formation model unit established:

[0119]

[0120] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0121] In one embodiment, a three-dimensional finite difference method is used to perform a numerical simulation of the acoustic transit time logging response on a pre-established fracture formation model to obtain the acoustic transit time porosity, including:

[0122] The numerical simulation unit is used for numerical simulation to obtain the sound wave time difference.

[0123] First analysis unit, applying AC_n = (AC-103.675·VSH) / (1-VSH) and Obtain the sonic transit time porosity.

[0124] In one embodiment, the Monte Carlo method is used to perform numerical simulation of neutron logging response on a pre-established fracture formation model to obtain neutron porosity, including:

[0125] Neutron simulation unit, used for numerical simulation to obtain neutrons.

[0126] The second analysis unit applies CNL_n = (CNL-26.2·VSH) / (1-VSH) and Get the neutron porosity.

[0127] In one embodiment, the maximum value of the acoustic transit time porosity and the neutron porosity is used as the fracture formation porosity, including:

[0128] an analysis unit for comparing neutron porosity and sonic transit time porosity;

[0129] The fracture formation porosity unit is used to take the maximum value as the final fracture formation porosity.

[0130] In one embodiment, comparing neutron porosity and sonic transit time porosity comprises:

[0131]

[0132]

[0133]

[0134]

[0135]

[0136] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0137] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 7As shown. The computer device includes a processor, a memory, a network interface and a database connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store periodic task allocation data, such as configuration files, theoretical operating parameters and theoretical deviation value ranges, task attribute information, etc. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for determining the porosity of a fractured formation is implemented.

[0138] Those skilled in the art can understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0139] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0140] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0141] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0142] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0143] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0144] In one embodiment, when the processor executes the computer program, before the step of applying the three-dimensional finite difference method to the pre-established fracture formation model to perform a numerical simulation of the acoustic time difference logging response and obtaining the acoustic time difference porosity, the method includes:

[0145] The fracture formation model established is:

[0146]

[0147] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0148] In one embodiment, when the processor executes the computer program, the three-dimensional finite difference method is used to perform a numerical simulation of the acoustic transit time logging response on a pre-established fracture formation model to obtain the acoustic transit time porosity, including:

[0149] The acoustic time difference is obtained by numerical simulation;

[0150] Apply AC_n = (AC-103.675·VSH) / (1-VSH) and Obtain the sonic transit time porosity.

[0151] In one embodiment, when the processor executes the computer program, the Monte Carlo method is used to perform a numerical simulation of the neutron logging response on a pre-established fracture formation model to obtain the neutron porosity, including:

[0152] Neutrons were obtained by numerical simulation;

[0153] Apply CNL_n = (CNL-26.2·VSH) / (1-VSH) and Get the neutron porosity.

[0154] In one embodiment, when the processor executes the computer program, the maximum value of the acoustic time difference porosity and the neutron porosity is used as the fracture formation porosity, including:

[0155] Compare neutron porosity and sonic transit time porosity;

[0156] The maximum value is taken as the final fracture formation porosity.

[0157] In one embodiment, the processor executes the computer program to compare the neutron porosity and the sonic transit time porosity, including:

[0158]

[0159]

[0160]

[0161]

[0162]

[0163] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0164] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0165] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0166] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0167] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0168] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0169] In one embodiment, when the computer program is executed by a processor, the step of applying a three-dimensional finite difference method to a pre-established fracture formation model to perform a numerical simulation of the acoustic transit time logging response to obtain the acoustic transit time porosity includes:

[0170] The fracture formation model established is:

[0171]

[0172] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0173] In one embodiment, when the computer program is executed by a processor, a three-dimensional finite difference method is used to perform a numerical simulation of the acoustic transit time logging response on a pre-established fracture formation model to obtain the acoustic transit time porosity, including:

[0174] The acoustic time difference is obtained by numerical simulation;

[0175] Apply AC_n = (AC-103.675·VSH) / (1-VSH) and Obtain the sonic transit time porosity.

[0176] In one embodiment, when the computer program is executed by the processor, the Monte Carlo method is used to perform a numerical simulation of neutron logging response on a pre-established fracture formation model to obtain neutron porosity, including:

[0177] Neutrons were obtained by numerical simulation;

[0178] Apply CNL_n = (CNL-26.2·VSH) / (1-VSH) and Get the neutron porosity.

[0179] In one embodiment, when the computer program is executed by a processor, the maximum value of the acoustic time difference porosity and the neutron porosity is used as the fracture formation porosity, including:

[0180] Compare neutron porosity and sonic transit time porosity;

[0181] The maximum value is taken as the final fracture formation porosity.

[0182] In one embodiment, the computer program, when executed by a processor, implements comparing neutron porosity and sonic transit time porosity, comprising:

[0183]

[0184]

[0185]

[0186]

[0187]

[0188] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0189] In one embodiment, a computer program is provided. When the computer program is executed by a processor, the following steps are implemented:

[0190] Obtaining numerical simulation parameters, which include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fractures, and mud neutron in fractures;

[0191] The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity.

[0192] The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity.

[0193] The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

[0194] In one embodiment, when the computer program is executed by a processor, the step of applying a three-dimensional finite difference method to a pre-established fracture formation model to perform a numerical simulation of the acoustic transit time logging response to obtain the acoustic transit time porosity includes:

[0195] The fracture formation model established is:

[0196]

[0197] in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

[0198] In one embodiment, when the computer program is executed by a processor, a three-dimensional finite difference method is used to perform a numerical simulation of the acoustic transit time logging response on a pre-established fracture formation model to obtain the acoustic transit time porosity, including:

[0199] The acoustic time difference is obtained by numerical simulation;

[0200] Apply AC_n = (AC-103.675·VSH) / (1-VSH) and Obtain the sonic transit time porosity.

[0201] In one embodiment, when the computer program is executed by the processor, the Monte Carlo method is used to perform a numerical simulation of neutron logging response on a pre-established fracture formation model to obtain neutron porosity, including:

[0202] Neutrons were obtained by numerical simulation;

[0203] Apply CNL_n = (CNL-26.2·VSH) / (1-VSH) and Get the neutron porosity.

[0204] In one embodiment, when the computer program is executed by a processor, the maximum value of the acoustic time difference porosity and the neutron porosity is used as the fracture formation porosity, including:

[0205] Compare neutron porosity and sonic transit time porosity;

[0206] The maximum value is taken as the final fracture formation porosity.

[0207] In one embodiment, the computer program, when executed by a processor, implements comparing neutron porosity and sonic transit time porosity, comprising:

[0208]

[0209]

[0210]

[0211]

[0212]

[0213] in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

[0214] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0215] The various embodiments in the present disclosure are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0216] The protection scope of the present disclosure is not limited to the above-mentioned embodiments. Obviously, those skilled in the art can make various changes and modifications to the present disclosure without departing from the scope and spirit of the present disclosure. If these changes and modifications fall within the scope of the claims of the present disclosure and their equivalents, the intention of the present disclosure also includes these changes and modifications.

Claims

1. A method for determining porosity of fractured formations, characterized in that: The method for determining the porosity of fractured formations comprises: Acquiring numerical simulation parameters, the numerical simulation parameters including: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fracture, and mud neutron in fracture; The three-dimensional finite difference method is used to numerically simulate the acoustic transit time logging response of the pre-established fracture formation model to obtain the acoustic transit time porosity. The Monte Carlo method is used to numerically simulate the neutron logging response of the pre-established fracture formation model to obtain the neutron porosity. The maximum value of the sonic transit time porosity and the neutron porosity is taken as the fracture formation porosity.

2. The method for determining the porosity of fractured formations according to claim 1, characterized in that: Before the step of applying the three-dimensional finite difference method to the pre-established fracture formation model to perform a numerical simulation of the acoustic time difference logging response to obtain the acoustic time difference porosity, the method includes: The fracture formation model established is: in: are fracture formation porosity, fracture porosity and bedrock porosity, all in units of f; V, V f are the total volume and the fracture volume, both in m 3 ; W f is the crack width, in m; θ is the crack inclination, in degrees.

3. The method for determining the porosity of fractured formations according to claim 2, characterized in that: The three-dimensional finite difference method is used to perform numerical simulation of acoustic time difference logging response on a pre-established fracture formation model to obtain acoustic time difference porosity, including: The acoustic time difference is obtained by numerical simulation; application and The sonic transit time porosity is obtained.

4. The method for determining the porosity of fractured formations according to claim 2, characterized in that: The method of applying the Monte Carlo method to the pre-established fracture formation model to perform a neutron logging response numerical simulation to obtain the neutron porosity includes: Neutrons were obtained by numerical simulation; application and The neutron porosity is obtained.

5. The method for determining the porosity of fractured formations according to claim 1, characterized in that: The method of taking the maximum value of the acoustic transit time porosity and the neutron porosity as the fracture formation porosity comprises: comparing the neutron porosity and the sonic transit time porosity; The maximum value is taken as the final porosity of the fracture formation.

6. The method for determining the porosity of fractured formations according to claim 5, characterized in that: The comparing the neutron porosity and the sonic transit time porosity comprises: in: and is the porosity calculated by neutron and the porosity calculated by sonic travel time, both in %; CNL_n and AC_n are the neutron and sonic travel time without mud influence, in % and μs / ft respectively; CNL and AC are the neutron and sonic travel time, in % and μs / ft respectively; VSH is the mud content, when VSH is less than 0, it is assigned a value of 0, in f; KTH is uranium-free gamma, in API.

7. A device for determining porosity of fractured formations, characterized in that: The device for determining the porosity of fractured formations comprises: An acquisition unit is used to acquire numerical simulation parameters, wherein the numerical simulation parameters include: bedrock formation porosity, fracture width, fracture inclination, bedrock acoustic wave time difference, bedrock neutron, mud acoustic wave time difference in fracture, and mud neutron in fracture; The sonic transit time porosity unit is used to numerically simulate the sonic transit time logging response of the pre-established fracture formation model using the three-dimensional finite difference method to obtain the sonic transit time porosity; Neutron porosity unit, used to apply Monte Carlo method to the pre-established fracture formation model, to perform numerical simulation of neutron logging response and obtain neutron porosity; The fractured formation porosity unit is used to take the maximum value of the acoustic wave time difference porosity and the neutron porosity as the fractured formation porosity.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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