Fractured reservoir fracture porosity change evaluation method and device

Abstract

The invention discloses a fractured reservoir fracture porosity change evaluation method and device, and the method comprises the steps: calculating fracture porosity for a pre-fracturing scene and a post-fracturing scene for a processing depth, and obtaining the fracture porosity of the pre-fracturing scene and the fracture porosity of the post-fracturing scene; determining fracture porosity change data according to the fracture porosity of the scene before fracturing and the fracture porosity of the scene after fracturing; the step of calculating the fracture porosity comprises the substeps that according to sound wave array logging data of the processing depth, the first sound wave speed of the target radial depth is obtained through inversion calculation; according to the first sound wave speed and the second sound wave speed, performing inversion calculation to obtain target fracture density; the second sound wave speed is obtained through forward modeling calculation according to a theoretical model; and calculating the fracture porosity according to the target fracture density and the fracture aspect ratio. In this way, quantification of the change of the fracture porosity before and after fracturing is achieved, and the change condition of the fracture porosity of the fractured reservoir can be effectively evaluated.

Description

Technical Field

[0001] The present application relates to the field of well logging technology, and in particular to a method, device, computing equipment, computer storage medium and computer program product for evaluating changes in fracture porosity of a fractured reservoir. Background Art

[0002] As the exploration and development of offshore reservoirs continues to increase, the focus of exploration work has gradually shifted to unconventional reservoirs such as low porosity and permeability and shale oil. Unconventional reservoirs have the characteristics of low porosity, low permeability, and strong heterogeneity. In order to obtain industrial oil and gas flows, large-scale volume fracturing is usually required, so fracturing has become a key technical means for the effective exploration and development of unconventional reservoirs. Whether volume fracturing can effectively open the reservoir and thus open the seepage channel for oil and gas production requires an evaluation of the artificial fractures produced by reservoir transformation. Among them, how to evaluate the porosity changes before and after reservoir fracturing is a difficult problem in the evaluation of reservoir fracturing effects.

[0003] At present, the commonly used porosity calculation methods are mainly based on sonic logging, density logging, resistivity logging, nuclear magnetic resonance logging, etc., to achieve porosity evaluation of conventional reservoirs. However, actual rocks usually contain both pores and fractures. Fractures are more developed in unconventional reservoirs, which is an important factor affecting the increase of reserves and production in unconventional low-permeability reservoirs. However, the commonly used porosity calculation methods are not suitable for unconventional reservoirs with complex pore structures. There is no more suitable quantitative evaluation method for the evaluation of fracture porosity changes in unconventional fracturing reservoirs. Summary of the invention

[0004] In view of the above problems, the present application is proposed to provide a method, apparatus, computing device, computer storage medium and computer program product for evaluating fracture porosity changes in fractured reservoirs that overcome the above problems or at least partially solve the above problems.

[0005] According to one aspect of the present application, a method for evaluating changes in fracture porosity of a fractured reservoir is provided, comprising: For the treatment depth, the fracture porosity is calculated for the pre-fracture scenario and the post-fracture scenario respectively, and the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario are obtained; Determine fracture porosity change data according to fracture porosity before fracturing and fracture porosity after fracturing; The calculation of fracture porosity specifically includes: The first acoustic wave velocity at the target radial depth is obtained by inversion calculation based on the acoustic array logging data at the processing depth; According to the first acoustic wave velocity and the second acoustic wave velocity, the target fracture density is obtained by inversion calculation; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; The fracture porosity is calculated based on the target fracture density and fracture aspect ratio.

[0006] Optionally, the first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, and the first acoustic wave velocity at the target radial depth is obtained by inversion calculation according to the acoustic wave array logging data of the processing depth further includes: The full-wave data of longitudinal waves and the full-wave data of shear waves in the acoustic array logging data are sequentially determined as the acoustic wave data to be processed; Perform inversion calculation on the acoustic wave data to be processed to obtain the acoustic wave velocity at the target radial depth; Wherein, when the acoustic wave data to be processed is longitudinal full-wave data, the acoustic wave velocity obtained by inversion calculation is the first longitudinal wave velocity; when the acoustic wave data to be processed is shear full-wave data, the acoustic wave velocity obtained by inversion calculation is the first shear wave velocity; The inversion calculation of the processed acoustic wave data further includes: The formation acoustic wave velocity is calculated based on the acoustic wave data to be processed; A radial velocity model is constructed according to the formation acoustic wave velocity, the acoustic wave velocity of part or all radial depths in the radial velocity model is adjusted, and a reference travel time for the acoustic wave to propagate to the target receiver is calculated based on the adjusted radial velocity model; wherein the acoustic wave type corresponding to the acoustic wave velocity in the radial velocity model is consistent with the acoustic wave type corresponding to the formation acoustic wave velocity; When the reference travel time matches the measured travel time of the acoustic wave propagating to the target receiver, the acoustic wave velocity at the target radial depth is obtained from the adjusted radial velocity model.

[0007] Optionally, according to the first acoustic wave velocity and the second acoustic wave velocity, inversion calculation to obtain the target fracture density further includes: Constructing an inversion objective function that relates the first acoustic wave velocity and the second acoustic wave velocity; The parameters to be inverted are set, and the second acoustic wave velocity and the inversion objective function are calculated according to the set parameters to be inverted; The first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, the second acoustic wave velocity includes a second longitudinal wave velocity and a second transverse wave velocity, and the parameters to be inverted include fracture density and fluid modulus of rock matrix; When the calculation result of the inversion objective function meets the preset conditions, the set fracture density is determined as the target fracture density.

[0008] Optionally, calculating the second acoustic wave velocity according to the set parameters to be inverted further includes: Analyze the logging data to obtain the original formation porosity and formation mud content; The bulk modulus and shear modulus of the rock matrix are calculated based on the original formation porosity, formation mud content, acoustic velocity and density of hard minerals, and acoustic velocity and density of soft minerals; The bulk modulus and shear modulus of the rock matrix and the set parameters to be inverted are input into the theoretical model, and the second acoustic wave velocity at the target radial depth is forward calculated.

[0009] Optionally, the inversion objective function is specifically a mean square error function.

[0010] Optionally, constructing the radial velocity model according to the formation acoustic wave velocity further includes: The acoustic wave velocity at each radial depth within a preset range of distance from the wellbore wall is set to be consistent with the formation acoustic wave velocity, thereby obtaining a radial velocity model.

[0011] According to another aspect of the present application, a device for evaluating changes in fracture porosity of a fractured reservoir is provided, comprising: A calculation module is used to calculate the fracture porosity for the treatment depth, the pre-fracture scenario and the post-fracture scenario, respectively, to obtain the fracture porosity for the pre-fracture scenario and the fracture porosity for the post-fracture scenario; An evaluation module, for determining fracture porosity change data based on fracture porosity of a pre-fracture scenario and fracture porosity of a post-fracture scenario; The calculation module is further used to: The first acoustic wave velocity at the target radial depth is obtained by inversion calculation based on the acoustic array logging data at the processing depth; According to the first acoustic wave velocity and the second acoustic wave velocity, the target fracture density is obtained by inversion calculation; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; The fracture porosity is calculated based on the target fracture density and fracture aspect ratio.

[0012] Optionally, the first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity; The calculation module is further used to: The full-wave data of longitudinal waves and the full-wave data of shear waves in the acoustic array logging data are sequentially determined as the acoustic wave data to be processed; Perform inversion calculation on the acoustic wave data to be processed to obtain the acoustic wave velocity at the target radial depth; Wherein, when the acoustic wave data to be processed is longitudinal full-wave data, the acoustic wave velocity obtained by inversion calculation is the first longitudinal wave velocity; when the acoustic wave data to be processed is shear full-wave data, the acoustic wave velocity obtained by inversion calculation is the first shear wave velocity; The calculation module is further used to: The formation acoustic wave velocity is calculated based on the acoustic wave data to be processed; A radial velocity model is constructed according to the formation acoustic wave velocity, the acoustic wave velocity of part or all radial depths in the radial velocity model is adjusted, and a reference travel time for the acoustic wave to propagate to the target receiver is calculated based on the adjusted radial velocity model; wherein the acoustic wave type corresponding to the acoustic wave velocity in the radial velocity model is consistent with the acoustic wave type corresponding to the formation acoustic wave velocity; When the reference travel time matches the measured travel time of the acoustic wave propagating to the target receiver, the acoustic wave velocity at the target radial depth is obtained from the adjusted radial velocity model.

[0013] Optionally, the calculation module is further configured to: Constructing an inversion objective function that relates the first acoustic wave velocity and the second acoustic wave velocity; The parameters to be inverted are set, and the second acoustic wave velocity and the inversion objective function are calculated according to the set parameters to be inverted; The first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, the second acoustic wave velocity includes a second longitudinal wave velocity and a second transverse wave velocity, and the parameters to be inverted include fracture density and fluid modulus of rock matrix; When the calculation result of the inversion objective function meets the preset conditions, the set fracture density is determined as the target fracture density.

[0014] Optionally, the calculation module is further configured to: Analyze the logging data to obtain the original formation porosity and formation mud content; The bulk modulus and shear modulus of the rock matrix are calculated based on the original formation porosity, formation mud content, acoustic velocity and density of hard minerals, and acoustic velocity and density of soft minerals; The bulk modulus and shear modulus of the rock matrix and the set parameters to be inverted are input into the theoretical model, and the second acoustic wave velocity at the target radial depth is forward calculated.

[0015] Optionally, the inversion objective function is specifically a mean square error function.

[0016] Optionally, the calculation module is further configured to: The acoustic wave velocity at each radial depth within a preset range of distance from the wellbore wall is set to be consistent with the formation acoustic wave velocity, thereby obtaining a radial velocity model.

[0017] According to another aspect of the present application, there is provided a computing device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned method for evaluating the change of fracture porosity of a fractured reservoir.

[0018] According to another aspect of the present application, a computer storage medium is provided, wherein the storage medium stores at least one executable instruction, wherein the executable instruction enables a processor to execute operations corresponding to the above-mentioned method for evaluating fracture porosity changes in fractured reservoirs.

[0019] According to another aspect of the present application, a computer program product is provided, comprising at least one executable instruction, wherein the executable instruction enables a processor to execute operations corresponding to the above-mentioned method for evaluating fracture porosity changes in fractured reservoirs.

[0020] According to the method, device, computing equipment, computer storage medium and computer program product for evaluating the change of fracture porosity of a fractured reservoir provided in the embodiments of the present application, the method comprises: calculating the fracture porosity for the treatment depth, for the pre-fracture scenario and the post-fracture scenario respectively, to obtain the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario; determining the fracture porosity change data according to the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario; wherein calculating the fracture porosity specifically comprises: obtaining the first acoustic wave velocity of the target radial depth by inversion calculation according to the acoustic wave array logging data of the treatment depth; obtaining the target fracture density by inversion calculation according to the first acoustic wave velocity and the second acoustic wave velocity; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; and calculating the fracture porosity according to the target fracture density and the fracture aspect ratio. Through the above method, the quantitative change of fracture porosity before and after fracturing is achieved, the change of fracture porosity of the fractured reservoir can be effectively evaluated, and the evaluation of the fracturing effect near the wellbore can be realized. The above method has good application effect and high applicability, and provides a new idea for the evaluation of fracturing effect of low permeability reservoirs.

[0021] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 A flow chart of a method for evaluating fracture porosity changes in a fractured reservoir provided in an embodiment of the present application is shown; Figure 2 It is a schematic diagram of the fracture theory model and the pore theory model; Figure 3This is the evaluation result diagram of the change of fracture porosity of a low-permeability reservoir before and after fracturing at sea; Figure 4 The functional structure diagram of the device for evaluating the change in fracture porosity of a fractured reservoir provided in an embodiment of the present application is shown; Figure 5 A schematic diagram of the structure of a computing device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0023] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0024] Figure 1 FIG. 1 is a flow chart of a method for evaluating the change in fracture porosity of a fractured reservoir provided in an embodiment of the present application. Figure 1 As shown, the method comprises the following steps: Step S110 , for the treatment depth, respectively for the pre-fracture scenario and the post-fracture scenario, the fracture porosity is calculated to obtain the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario.

[0025] Step S120, determining fracture porosity change data according to the fracture porosity of the scene before fracturing and the fracture porosity of the scene after fracturing.

[0026] The treatment depth may be one or more depths within the depth range of interest. For the treatment depth, the fracture porosity of the scene before fracturing and the fracture porosity of the scene after fracturing are calculated respectively, and the difference between the two is taken to obtain the change data of the fracture porosity before and after fracturing at the treatment depth.

[0027] The specific implementation method of calculating the fracture porosity includes the following steps: Step S1101, based on the acoustic array logging data of the processing depth, inversion calculation is performed to obtain the first acoustic wave velocity at the target radial depth.

[0028] By performing array acoustic logging within the depth interval of interest, acoustic array logging data at various depths can be obtained, and through a series of calculations, the first acoustic wave velocity at the target radial depth at the processing depth can be obtained.

[0029] The radial direction refers to the direction perpendicular to the axial direction of the wellbore. In the wellbore, the radial direction is the direction extending outward from the wellbore and is usually used to describe the lateral propagation and detection range of sound waves in the formation.

[0030] Step S1102, obtaining the target fracture density by inversion calculation according to the first acoustic wave velocity and the second acoustic wave velocity; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model.

[0031] Step S1103, calculating the fracture porosity according to the target fracture density and the fracture aspect ratio.

[0032] The first acoustic wave velocity is calculated based on real logging data, and the second acoustic wave velocity is calculated based on a theoretical model. The second acoustic wave velocity is related to the parameters to be inverted in the inversion calculation. The parameters to be inverted include at least fracture density. The parameters to be inverted are set, and the second acoustic wave velocity is calculated based on the set parameters to be inverted. When it is determined that the inversion target condition is met according to the first acoustic wave velocity and the second acoustic wave velocity, the set fracture density at this time is the inversion result (i.e., the target fracture density).

[0033] When the fracture density is known, the fracture porosity is calculated using the fracture density and fracture aspect ratio. The derivation process of the calculation method is as follows: Figure 2 is a schematic diagram of the fracture theory model and the pore theory model. The fracture surface radius of fracture 1 is , the radius of pore 2 is R, and the pore-crack theory assumes that the crack is coin-shaped (i.e., a flat ellipsoid), and its three semi-axes are , , , the three satisfy the following relationship: According to the ellipsoid volume calculation formula, the volume occupied by a single crack is calculated as shown in formula (1): (1); in, is the volume occupied by a single crack, is the radius of the crack surface, and .

[0034] Assume that in the reference volume there is If there are cracks in the same shape and size, the ratio of the total crack volume to the reference volume is the crack porosity. The calculation method of the crack porosity is shown in formula (2): (2); in, is the fracture porosity, is the reference volume. Then, the numerator and denominator of formula (2) are multiplied by the fracture surface radius. , in order to convert the calculation formula of fracture porosity, the calculation method of fracture porosity after conversion is shown in formula (3): (3); in, is the crack density, r is the target radial depth, is the crack aspect ratio.

[0035] Substituting the calculated target fracture density and fracture aspect ratio into the above formula (3), the fracture porosity at the treatment depth can be obtained. At the treatment depth, for the pre-fracture scenario and the post-fracture scenario, the fracture porosity is calculated in the above manner to obtain the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario. By comparing the two, the fracture porosity change data at the treatment depth can be determined.

[0036] According to the method for evaluating the change of fracture porosity of a fractured reservoir provided in this embodiment, the quantification of the change of fracture porosity before and after fracturing is achieved. Based on the array acoustic logging data before and after fracturing, the first acoustic wave velocity of the radial depth of the formation is inverted, and the fracture density is obtained by combining the inversion technology based on the theoretical model. The fracture porosity before and after fracturing is calculated, and then the change of fracture porosity of the fractured reservoir in the radial direction of the formation is obtained. The change of fracture porosity of the fractured reservoir can be effectively evaluated, and the evaluation of the fracturing effect near the wellbore is achieved. The above method has good application effect and high applicability, and provides a new idea for the evaluation of the fracturing effect of low-permeability reservoirs.

[0037] In an optional manner, the method of an embodiment of the present application also includes: forming a pre-fracture fracture porosity curve according to the fracture porosity of the pre-fracture scenario at each treatment depth, and forming a post-fracture fracture porosity curve according to the fracture porosity of the post-fracture scenario at each treatment depth; aligning the pre-fracture fracture porosity curve and the post-fracture fracture porosity curve according to depth and then subtracting them to obtain fracture porosity change data for the entire depth range.

[0038] The first acoustic wave velocity includes a first longitudinal wave velocity and a first shear wave velocity, the first longitudinal wave velocity is obtained based on the longitudinal wave full wave data in the acoustic wave array logging data, and the first shear wave velocity is obtained based on the shear wave full wave data in the acoustic wave array logging data. According to the acoustic wave array logging data of the processing depth, the first acoustic wave velocity at the target radial depth is obtained by inversion calculation, and the specific implementation method of this step is as follows: The full-wave data of longitudinal waves and the full-wave data of shear waves in the acoustic array logging data are sequentially determined as the acoustic wave data to be processed; Perform inversion calculation on the acoustic wave data to be processed to obtain the acoustic wave velocity at the target radial depth; Among them, when the acoustic wave data to be processed is longitudinal full-wave data, the acoustic wave velocity obtained by inversion calculation is the first longitudinal wave velocity; when the acoustic wave data to be processed is shear full-wave data, the acoustic wave velocity obtained by inversion calculation is the first shear wave velocity.

[0039] The inversion calculation of the processed acoustic wave data further includes: The formation acoustic wave velocity is calculated based on the acoustic wave data to be processed; A radial velocity model is constructed according to the formation acoustic wave velocity, the acoustic wave velocity of part or all radial depths in the radial velocity model is adjusted, and a reference travel time for the acoustic wave to propagate to the target receiver is calculated based on the adjusted radial velocity model; wherein the acoustic wave type corresponding to the acoustic wave velocity in the radial velocity model is consistent with the acoustic wave type corresponding to the formation acoustic wave velocity; When the reference travel time matches the measured travel time of the acoustic wave propagating to the target receiver, the acoustic wave velocity at the target radial depth is obtained from the adjusted radial velocity model.

[0040] In an optional manner, constructing the radial velocity model according to the formation acoustic wave velocity further includes: The acoustic wave velocity at each radial depth within a preset range of distance from the wellbore wall is set to be consistent with the acoustic wave velocity of the formation, and a radial velocity model is obtained. That is, when the acoustic wave data to be processed is full-wave longitudinal wave data, the longitudinal wave velocity at each radial depth included in the radial velocity model is set according to the longitudinal wave velocity of the formation; when the acoustic wave data to be processed is full-wave shear wave data, the shear wave velocity at each radial depth included in the radial velocity model is set according to the shear wave velocity of the formation.

[0041] In an optional manner, before constructing the radial velocity model according to the formation acoustic wave velocity, the method further includes: According to the formation acoustic wave velocity, the travel time of the acoustic wave propagating to the target receiver in the array acoustic logging instrument is calculated to obtain the initial reference travel time. Accordingly, if the initial reference travel time is smaller than the measured travel time, the radial velocity model is constructed according to the formation acoustic wave velocity and the subsequent steps are executed. If the initial reference travel time is consistent with the measured travel time, it means that the acoustic wave velocity has not changed in the radial direction, and the radial velocity model can be directly determined, and the acoustic wave velocity at each radial depth is consistent. Similarly, the acoustic wave type corresponding to the formation acoustic wave velocity is consistent with the acoustic wave type corresponding to the radial velocity model.

[0042] The following takes the to-be-processed acoustic wave data as longitudinal full-wave data as an example to illustrate the specific process of the inversion calculation of the embodiment of the present application: First, the formation P-wave velocity is calculated based on the P-wave full-wave data. Specifically, the slowness-time correlation method is used to obtain the formation P-wave velocity at the processing depth. The slowness-time correlation method is expressed as follows: (4); in, is the two-dimensional correlation function, For time, The first The time domain waveform of a receiving transducer (i.e., receiver), is the total number of receiving transducers, is the spacing between the receiving transducers, For speed, is the time window, For the position of the time window, the two-dimensional correlation function is calculated for the entire waveform or a certain period in the waveform and a given speed interval. The corresponding The value is used to obtain the formation compressional wave velocity.

[0043] Then, according to the formation P-wave velocity, the initial reference travel time of the P-wave propagating to the target receiver in the array logging tool is calculated. The target receiver can be any receiver in the array logging tool. The specific calculation method is shown in formula (5): (5); in, is the formation compressional wave velocity calculated according to the above steps, which is the velocity at the maximum radial penetration depth. is the initial reference travel time, is the depth corresponding to the target receiver, S is the depth corresponding to the sound source, is the propagation time of the longitudinal wave in the fluid in the well.

[0044] For formations where the P-wave velocity does not vary radially, the reference travel time is consistent with the measured travel time, which is the travel time of the P-wave transmitted to the target receiver in the array logging tool calculated based on the actual logging data. When the P-wave velocity increases radially, the measured travel time is the time it takes for the ray to enter the formation from shallow to deep and then refract back. is the velocity at the maximum penetration depth. Therefore, the initial reference travel time calculated according to the above formula (5) is smaller than the measured travel time, that is, the measured travel time lags behind the initial reference travel time.

[0045] Accordingly, if the initial reference travel time is smaller than the measured travel time, the relevant processing is continued to obtain the first P-wave velocity of the target radial depth. The specific processing method is as follows: for the preset range of radial depth, a radial velocity model is constructed according to the P-wave velocity of the formation. The P-wave velocity of each radial depth in the radial velocity model is set to the calculated P-wave velocity of the formation. The radial velocity model is used for forward calculation of the reference travel time, which is specifically calculated according to the ray tracing method. The P-wave velocity of some or all radial depths in the radial velocity model is adjusted, and the reference travel time is calculated by the ray tracing method for the adjusted radial velocity model. When the reference travel time is close to or equal to the measured travel time, the adjusted radial velocity model is the absolute velocity profile obtained, from which the target radial depth is extracted. The first longitudinal wave velocity .

[0046] For example, the preset range is from zero to infinity in distance from the wellbore wall. If the measured travel time lags behind the initial reference travel time, in order to make the measured travel time coincide with or approach the reference travel time, the P-wave velocity at 0m-drm near the wellbore wall is reduced to v(z)-dv, and the P-wave velocities at other radial depths remain unchanged. The reference travel time is recalculated according to the adjusted radial velocity model; if there is a gap between the measured travel time and the recalculated reference travel time, the P-wave velocity at 0m-drm near the wellbore wall is further reduced to v(z)-2dv, and the P-wave velocity at drm-2drm is reduced to v(z)-dv, and the P-wave velocities at other radial depths remain unchanged. Repeat the update of the radial velocity model until the measured travel time coincides with or approaches the calculated reference travel time. At this time, the radial velocity model is the absolute velocity profile required, that is, the P-wave velocity that changes with radial depth is obtained. Among them, dr and dv are the distance adjustment granularity and the velocity adjustment granularity, respectively, which can be set according to actual needs.

[0047] It should be noted that by processing the full-wave shear wave data in the above-mentioned calculation and processing method, a radial velocity model containing the shear wave velocity at each radial depth can be obtained, from which the target radial depth can be extracted. The first shear wave velocity The specific implementation method of obtaining the first shear wave velocity based on the inversion of the shear wave full-wave data will not be described in detail.

[0048] In an optional manner, a specific implementation method of inverting and calculating the fracture density according to the first acoustic wave velocity and the second acoustic wave velocity is as follows: Constructing an inversion objective function that relates the first acoustic wave velocity and the second acoustic wave velocity; The parameters to be inverted are set, and the second acoustic wave velocity and the inversion objective function are calculated according to the set parameters to be inverted; The first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, the second acoustic wave velocity includes a second longitudinal wave velocity and a second transverse wave velocity, and the parameters to be inverted include fracture density and fluid modulus of rock matrix; When the calculation result of the inversion objective function meets the preset conditions, the set fracture density is determined as the target fracture density.

[0049] The specific implementation method of calculating the second sound wave velocity is as follows: Analyze the logging data to obtain the original formation porosity and formation mud content; The bulk modulus and shear modulus of the rock matrix are calculated based on the original formation porosity, formation mud content, acoustic velocity and density of hard minerals, and acoustic velocity and density of soft minerals; The bulk modulus and shear modulus of the rock matrix and the set parameters to be inverted are input into the theoretical model, and the second acoustic wave velocity at the target radial depth is forward calculated.

[0050] Specifically, firstly, the original formation porosity is calculated based on the density logging data at the processing depth. The specific calculation method is shown in formula (6): (6); in, is the original formation porosity, is the density of rock skeleton minerals, in g / cm3; is the density of the pore fluid, in g / cm3; It is the formation density obtained by density logging, in g / cm3.

[0051] Secondly, the formation mud content is calculated based on the natural gamma logging data at the processing depth. The specific calculation method is shown in formula (7): (7); in, is the formation mud content, is the maximum value of the natural gamma logging curve, is the minimum value of the natural gamma logging curve, Indicates the natural gamma logging curve value at the processing depth.

[0052] Then, the bulk modulus and shear modulus of the rock matrix are calculated according to the time-average method and Wood's formula. The parameters required for the calculation include: original formation porosity, formation mud content, acoustic velocity and density of hard minerals, acoustic velocity and density of soft minerals. The specific calculation method is as follows: Step 1: Calculate the P-wave velocity in the rock matrix , shear wave velocity And density , the calculation method is shown in formulas (8) and (9): (8); (9); in, is the formation mud content, is the original formation porosity, ( , ) are the longitudinal wave velocities of soft minerals and hard minerals respectively, ( , ) are the shear wave velocities of soft minerals and hard minerals, respectively. ( , ) are the densities of soft minerals and hard minerals respectively.

[0053] Step 2: Based on the longitudinal wave velocity of the rock matrix , shear wave velocity And density , calculate the bulk modulus and shear modulus of the rock matrix, and the calculation method is shown in formula (10): (10); in, is the bulk modulus of the rock matrix, is the shear modulus of the rock matrix.

[0054] Step 3: Input the bulk modulus and shear modulus of the rock matrix and the parameters to be inverted into the theoretical model. The theoretical model is specifically: a unified theoretical model of elastic fluctuations in porous and fractured media, and forward calculation of the target radial depth The second longitudinal wave velocity at and the second shear wave velocity , the calculation method is shown in formula (11): (11); Among them, Re(∗) represents the real part operator of complex numbers; and are the density of pore fluid and the density of saturated rock, respectively; is the equivalent seepage density, ,in, and are angular frequency and fluid viscosity, respectively, That is, the imaginary unit; is the dynamic permeability, ,in, is the critical frequency of Biot macroscopic flow, is the static Darcy permeability; is the low-frequency P-wave modulus of saturated rock, ,in, and are the bulk modulus and shear modulus of saturated rock, respectively; C = αM , α is the Biot-Wills coefficient, and is the storage modulus, ,in, and are the bulk modulus and fluid modulus of the rock matrix, is the fracture squirting flow function, and is related to the fracture density Related, The expression of is shown in formula (12): (12); in, is the ratio of crack size to pore size, and its calculation method is shown in formula (13): (13); in, ; is the crack aspect ratio; is the fluid modulus of the rock matrix, is the bulk modulus of the dry skeleton of the porous medium; , and are the shear modulus, bulk modulus and Poisson's ratio of porous fracture media when squeezing flow is not considered, calculated by Biot consistent theory, According to Biot's consistency theory and the shear modulus of the rock matrix Calculated shear modulus of saturated rock ,in, .

[0055] Afterwards, the inversion objective function is calculated according to the first P-wave velocity, the first S-wave velocity, the second P-wave velocity and the second S-wave velocity. In an optional manner, the inversion objective function is specifically a mean square error function. and the fluid modulus of the rock matrix As two parameters to be inverted, the target radial depth of the low porosity and permeability reservoir calculated by forward modeling using the theoretical model is The second longitudinal wave velocity at and the second shear wave velocity The target radial depth obtained by inversion of radial velocity profile The first longitudinal wave velocity at and the first shear wave velocity , construct the mean square error objective function as shown in formula (14) ; (14); in, is the weight coefficient before the longitudinal wave variance, , According to the theoretical model and the established and Target radial depth calculated by forward modeling The second P-wave velocity and the second S-wave velocity at . The values ​​of the fracture density and the fluid modulus of the rock matrix are adjusted. Whenever they are adjusted to new values, the second P-wave velocity and the second S-wave velocity are calculated according to the theoretical model, and the inversion objective function is calculated. When the inversion objective function reaches the minimum value, it is determined that the theoretical data and the measured data are best fitted, and the values ​​of the fracture density and the fluid modulus of the rock matrix at this time are determined as the fracture density and the fluid modulus of the rock matrix in the actual reservoir. The fracture density at this time is the inversion result of the fracture density (i.e., the target fracture density).

[0056] According to the method for evaluating changes in fractured reservoir fracture porosity of the embodiment of the present application, the radial velocity profile technology is innovatively combined with the inversion technology of "the unified theory of elastic fluctuations in porous and fractured media", and the radial velocity profile inversion technology is used to calculate the radial longitudinal wave velocity and transverse wave velocity of the formation before and after fracturing respectively; based on the longitudinal and transverse wave velocities of the formation before and after fracturing, the mud content of the formation, and the original formation porosity, combined with density curves, natural gamma and other logging data, the inversion technology of "the unified theory of elastic fluctuations in porous and fractured media" is used to calculate the fracture porosity that changes with radial depth; the fracture porosity before and after fracturing is subtracted, so as to accurately evaluate the changes in fracture porosity of the fractured reservoir.

[0057] Figure 3 This is an evaluation result diagram of the change in fracture porosity of a low-permeability offshore reservoir before and after fracturing. From left to right, the first track is the lithology curve, the first curve is the gamma-ray logging curve, the second curve is the drill bit size BIT curve, and the third curve is the wellbore CAL curve. The second track is the resistivity curve, including curves at different resistivities. The third track is the porosity curve, the fourth track is the fracturing section, the fifth track is the depth track, the sixth track is the anisotropy comparison curve before and after fracturing, the seventh track is the Stoneley wave reflection coefficient curve before and after fracturing, the eighth track is the difference in radial velocity profiles before and after fracturing, and the ninth to sixteenth tracks are the changes in fracture porosity of the fractured reservoir at the target radial depth, which are obtained based on the array logging data processing of the corresponding receivers. is the identifier of the receiver, .

[0058] As shown in the figure, the fracturing sections of this well are 3031m-3032m, 3037m-3038m, and 3048m-3049m. According to the anisotropy, Stoneley wave reflection coefficient, and radial velocity profile processing results, it is shown that the areas where the reservoir in this well section undergoes significant changes before and after fracturing are mainly concentrated in 3027m-3034.5m, 3036m-3040m, and 3045m -3055m, the anisotropy in these three sections increased after fracturing, the Stoneley wave reflection coefficient was significantly enhanced, and the radial velocity profile changed significantly, indicating that the formation P-wave velocity decreased significantly along the radial direction, indicating that the reservoir was affected by the fracturing operation and fractures and micro-cracks were generated. At this time, the change in reservoir fracture porosity before and after fracturing increased significantly, which was consistent with the response of anisotropy, Stoneley wave reflection coefficient, and radial velocity profile. With the increase of radial depth, the change in fracture porosity decreased, which was consistent with the spatial development characteristics of fractures and micro-cracks. In the sections of 3034.5 m -3036m and 3040 m- 3045m, the anisotropy and radial velocity profile changed little after fracturing, indicating that the formation P-wave velocity did not change significantly along the radial direction, indicating that the reservoir was less affected by the fracturing operation. At this time, the change in reservoir fracture porosity before and after fracturing was small, which was consistent with the response of anisotropy and radial velocity profile. The above analysis demonstrates the correctness and effectiveness of the method for evaluating the change in fracture porosity of a fractured reservoir provided in the embodiments of the present application.

[0059] Figure 4 The functional structure diagram of the device for evaluating the change in fracture porosity of a fractured reservoir provided in an embodiment of the present application is shown. Figure 4 As shown, the device comprises: A calculation module 41 is used to calculate the fracture porosity for the treatment depth, the pre-fracture scenario and the post-fracture scenario, respectively, to obtain the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario; An evaluation module 42, for determining fracture porosity change data according to the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario; The calculation module 41 is further used for: The first acoustic wave velocity at the target radial depth is obtained by inversion calculation based on the acoustic array logging data at the processing depth; According to the first acoustic wave velocity and the second acoustic wave velocity, the target fracture density is obtained by inversion calculation; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; The fracture porosity is calculated based on the target fracture density and fracture aspect ratio.

[0060] In an optional manner, the first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity; The calculation module 41 is further used for: The full-wave data of longitudinal waves and the full-wave data of shear waves in the acoustic array logging data are sequentially determined as the acoustic wave data to be processed; Perform inversion calculation on the acoustic wave data to be processed to obtain the acoustic wave velocity at the target radial depth; When the acoustic wave data to be processed is longitudinal full-wave data, the acoustic wave velocity obtained by inversion calculation is the first longitudinal wave velocity; when the acoustic wave data to be processed is transverse full-wave data, the acoustic wave velocity obtained by inversion calculation is the first transverse wave velocity; wherein the calculation module 41 is further used for: The formation acoustic wave velocity is calculated based on the acoustic wave data to be processed; A radial velocity model is constructed according to the formation acoustic wave velocity, the acoustic wave velocity of part or all radial depths in the radial velocity model is adjusted, and a reference travel time for the acoustic wave to propagate to the target receiver is calculated based on the adjusted radial velocity model; wherein the acoustic wave type corresponding to the acoustic wave velocity in the radial velocity model is consistent with the acoustic wave type corresponding to the formation acoustic wave velocity; When the reference travel time matches the measured travel time of the acoustic wave propagating to the target receiver, the acoustic wave velocity at the target radial depth is obtained from the adjusted radial velocity model.

[0061] In an optional manner, the calculation module 41 is further used for: Constructing an inversion objective function that relates the first acoustic wave velocity and the second acoustic wave velocity; The parameters to be inverted are set, and the second acoustic wave velocity and the inversion objective function are calculated according to the set parameters to be inverted; The first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, the second acoustic wave velocity includes a second longitudinal wave velocity and a second transverse wave velocity, and the parameters to be inverted include fracture density and fluid modulus of rock matrix; When the calculation result of the inversion objective function meets the preset conditions, the set fracture density is determined as the target fracture density.

[0062] In an optional manner, the calculation module 41 is further used for: Analyze the logging data to obtain the original formation porosity and formation mud content; The bulk modulus and shear modulus of the rock matrix are calculated based on the original formation porosity, formation mud content, acoustic velocity and density of hard minerals, and acoustic velocity and density of soft minerals; The bulk modulus and shear modulus of the rock matrix and the set parameters to be inverted are input into the theoretical model, and the second acoustic wave velocity at the target radial depth is forward calculated.

[0063] In an optional manner, the inversion objective function is specifically a mean square error function.

[0064] In an optional manner, the calculation module 41 is further used for: The acoustic wave velocity at each radial depth within a preset range of distance from the wellbore wall is set to be consistent with the formation acoustic wave velocity, thereby obtaining a radial velocity model.

[0065] In summary, according to the device for evaluating the change in fracture porosity of a fractured reservoir provided in this embodiment, the quantification of the change in fracture porosity before and after fracturing is achieved. Based on the array acoustic logging data before and after fracturing, the first acoustic wave velocity of the radial depth of the formation is inverted, and the fracture density is obtained by combining the inversion technology based on the theoretical model, thereby obtaining the fracture porosity before and after fracturing, and then obtaining the change in fracture porosity of the fractured reservoir in the radial direction of the formation. This can effectively evaluate the change in fracture porosity of the fractured reservoir and realize the evaluation of the fracturing effect near the wellbore. The above method has good application effect and high applicability, and provides a new idea for the evaluation of the fracturing effect of low-permeability reservoirs.

[0066] An embodiment of the present application provides a non-volatile computer storage medium, which stores at least one executable instruction or computer program, which enables a processor to perform operations corresponding to the method for evaluating porosity changes in fractured reservoirs in any of the above method embodiments.

[0067] An embodiment of the present application provides a computer program product, which includes at least one executable instruction or computer program, which can enable a processor to perform operations corresponding to the method for evaluating porosity changes in fractured reservoirs in any of the above method embodiments.

[0068] Figure 5 A schematic diagram of the structure of an embodiment of a computing device of the present application is shown. The specific embodiment of the present application does not limit the specific implementation of the computing device.

[0069] like Figure 5 As shown, the computing device may include: a processor 502 , a communication interface 504 , a memory 506 , and a communication bus 508 .

[0070] The processor 502, the communication interface 504, and the memory 506 communicate with each other via a communication bus 508. The communication interface 504 is used to communicate with other devices such as a client or other server network elements. The processor 502 is used to execute a program 510, which can specifically execute the relevant steps in the embodiment of the above-mentioned method for evaluating the change in fracture porosity of a fractured reservoir for a computing device.

[0071] Specifically, the program 510 may include program codes, which include computer operation instructions.

[0072] The processor 502 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application. The one or more processors included in the computing device may be processors of the same type, such as one or more CPUs; or may be processors of different types, such as one or more CPUs and one or more ASICs.

[0073] The memory 506 is used to store the program 510. The memory 506 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0074] The program 510 can be specifically used to enable the processor 502 to execute the method for evaluating the change in the fractured reservoir fracture porosity in any of the above-mentioned method embodiments. The specific implementation of each step in the program 510 can refer to the corresponding descriptions in the corresponding steps and units in the embodiment for evaluating the change in the fractured reservoir fracture porosity, which will not be repeated here. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the above-described equipment and modules can refer to the corresponding process description in the above-mentioned method embodiment, which will not be repeated here.

[0075] The algorithm or display provided here are not inherently related to any specific computer, virtual system or other equipment. Various general systems can also be used together with the teaching based on this. According to the above description, it is obvious to construct the structure required for this type of system. In addition, the present application embodiment is not directed to any specific programming language yet. It should be understood that various programming languages ​​can be utilized to realize the content of the present application described here, and the above description of specific languages ​​is to disclose the best mode of implementation of the present application.

[0076] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0077] Similarly, it should be understood that in order to streamline the present application and aid in understanding one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the embodiments of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be interpreted as reflecting the following intention: the claimed application requires more features than the features explicitly recited in each claim. More specifically, as reflected in the claims, the inventive aspects lie in less than all the features of the single embodiment disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present application.

[0078] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and further may be divided into a plurality of submodules or subunits or subcomponents. All features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device so disclosed may be combined in any combination, except that at least some of such features and / or processes or units are mutually exclusive. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0079] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0080] The various component embodiments of the present application may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all functions of some or all components according to the embodiments of the present application. The present application may also be implemented as a device or apparatus program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program implementing the present application may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0081] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be constructed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present application may be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be understood as limitations on the order of execution.

Claims

1. A method for evaluating the change in porosity of fractured reservoirs, characterized in that: The method comprises: For the treatment depth, the fracture porosity is calculated for the pre-fracture scenario and the post-fracture scenario respectively, and the fracture porosity of the pre-fracture scenario and the fracture porosity of the post-fracture scenario are obtained; Determine fracture porosity change data according to fracture porosity before fracturing and fracture porosity after fracturing; Wherein, the calculation of fracture porosity specifically includes: Invert and calculate the first acoustic wave velocity at the target radial depth according to the acoustic wave array logging data at the processing depth; The target fracture density is obtained by inversion calculation according to the first acoustic wave velocity and the second acoustic wave velocity; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; The fracture porosity is calculated based on the target fracture density and the fracture aspect ratio.

2. The method for evaluating the change in fracture porosity of a fractured reservoir according to claim 1, characterized in that: The first acoustic wave velocity includes a first longitudinal wave velocity and a first shear wave velocity, and the inversion calculation to obtain the first acoustic wave velocity at the target radial depth based on the acoustic wave array logging data at the processing depth further includes: The full-wave data of longitudinal waves and the full-wave data of shear waves in the acoustic array logging data are sequentially determined as the acoustic wave data to be processed; Performing inversion calculation on the acoustic wave data to be processed to obtain the acoustic wave velocity at the target radial depth; Wherein, when the acoustic wave data to be processed is longitudinal full-wave data, the acoustic wave velocity obtained by inversion calculation is the first longitudinal wave velocity; when the acoustic wave data to be processed is shear full-wave data, the acoustic wave velocity obtained by inversion calculation is the first shear wave velocity; Wherein, performing inversion calculation on the acoustic wave data to be processed further comprises: Calculating the formation acoustic wave velocity according to the acoustic wave data to be processed; Constructing a radial velocity model according to the formation acoustic wave velocity, adjusting the acoustic wave velocity of part or all radial depths in the radial velocity model, and calculating a reference travel time for the acoustic wave to propagate to a target receiver according to the adjusted radial velocity model; wherein the acoustic wave type corresponding to the acoustic wave velocity in the radial velocity model is consistent with the acoustic wave type corresponding to the formation acoustic wave velocity; When the reference travel time matches the measured travel time of the acoustic wave propagating to the target receiver, the acoustic wave velocity at the target radial depth is obtained from the adjusted radial velocity model.

3. The method for evaluating the change in fracture porosity of a fractured reservoir according to claim 1, characterized in that: The inversion calculation to obtain the target fracture density according to the first acoustic wave velocity and the second acoustic wave velocity further comprises: Constructing an inversion objective function that relates the first acoustic wave velocity and the second acoustic wave velocity; The parameters to be inverted are set, and the second acoustic wave velocity and the inversion objective function are calculated according to the set parameters to be inverted; Wherein, the first acoustic wave velocity includes a first longitudinal wave velocity and a first transverse wave velocity, the second acoustic wave velocity includes a second longitudinal wave velocity and a second transverse wave velocity, and the parameters to be inverted include fracture density and fluid modulus of rock matrix; When the calculation result of the inversion objective function meets the preset conditions, the set fracture density is determined as the target fracture density.

4. The method for evaluating the change in fracture porosity of a fractured reservoir according to claim 3, characterized in that: The calculating the second acoustic wave velocity according to the set parameters to be inverted further comprises: Analyze the logging data to obtain the original formation porosity and formation mud content; The bulk modulus and shear modulus of the rock matrix are calculated based on the original formation porosity, formation mud content, acoustic velocity and density of hard minerals, and acoustic velocity and density of soft minerals; The bulk modulus and shear modulus of the rock matrix and the set parameters to be inverted are input into the theoretical model, and the second acoustic wave velocity at the target radial depth is forward calculated.

5. The method for evaluating the change in fracture porosity of a fractured reservoir according to claim 3, characterized in that: The inversion objective function is specifically a mean square error function.

6. The method for evaluating the change in fracture porosity of a fractured reservoir according to claim 2, characterized in that: The constructing of the radial velocity model according to the formation acoustic wave velocity further comprises: The acoustic wave velocity at each radial depth within a preset range of distance from the wellbore wall is set to be consistent with the formation acoustic wave velocity, thereby obtaining the radial velocity model.

7. A device for evaluating the change in porosity of fractured reservoirs, characterized in that: include: A calculation module is used to calculate the fracture porosity for the treatment depth, the pre-fracture scenario and the post-fracture scenario, respectively, to obtain the fracture porosity for the pre-fracture scenario and the fracture porosity for the post-fracture scenario; An evaluation module, for determining fracture porosity change data based on fracture porosity of a pre-fracture scenario and fracture porosity of a post-fracture scenario; The calculation module is further used for: Invert and calculate the first acoustic wave velocity at the target radial depth according to the acoustic wave array logging data at the processing depth; The target fracture density is obtained by inversion calculation according to the first acoustic wave velocity and the second acoustic wave velocity; wherein the second acoustic wave velocity is obtained by forward calculation according to the theoretical model; The fracture porosity is calculated based on the target fracture density and the fracture aspect ratio.

8. A computing device, characterized in that include: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to the method for evaluating changes in fracture porosity of a fractured reservoir according to any one of claims 1-6.

9. A computer storage medium, characterized in that The storage medium stores at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the method for evaluating changes in fracture porosity of a fractured reservoir according to any one of claims 1 to 6.

10. A computer program product, characterized in that The method comprises at least one executable instruction, wherein the executable instruction enables a processor to execute operations corresponding to the method for evaluating changes in fracture porosity of a fractured reservoir as claimed in any one of claims 1 to 6.

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