Pressing crack net depicting method and device, storage medium and processor

Abstract

The invention relates to the field of geological exploration, and discloses a fracturing fracture net depicting method and device, a storage medium and a processor, and the method comprises the steps: calculating the cumulative flow capability and the cumulative storage capability of a fracturing fracture net according to a tracer agent actual output curve; determining the number of main fractures in the fracture network based on the accumulated flow capacity and the accumulated storage capacity; establishing a tracer migration mathematical model according to the number of main fractures in the fracture network, and determining a target function based on the tracer migration mathematical model; fitting the tracer agent actual output curve based on the objective function to obtain a fitted tracer agent output curve, and obtaining the structural parameters of the main fracture in the fracture network based on the fitted tracer agent output curve. The structural parameters of the main crack in the fracturing crack net can be obtained, so that the accuracy of depicting the fracturing crack net can be improved.

Description

Technical Field

[0001] The present invention relates to the field of geological exploration technology, and in particular to a fracture network characterization method, a fracture network characterization device, a machine-readable storage medium, and a processor. Background Art

[0002] Horizontal well volume fracturing is a key technology for efficient shale oil and gas development. During the fracturing process, a complex fracture network is formed. This fracture network serves as the flow pathway connecting the reservoir and the wellbore, directly determining the effectiveness of shale oil and gas development. Therefore, characterizing and mapping this fracture network facilitates the rational development of shale oil and gas production systems and optimizes fracturing measures.

[0003] However, some commonly used methods cannot accurately depict and characterize the fracture network. For example, the method disclosed in CN109630104A injects a phase-separated chemical tracer into the formation along with the hydraulic fracturing fluid, takes samples regularly at the wellhead, detects the concentration of the chemical tracer in all samples, and plots the detected chemical tracer concentration data against the cumulative output data of the corresponding phase fluid. The volume of the tracer in the oil phase, gas phase, and water phase is obtained, respectively, to calculate the effective volume of the fracture. This solution does not obtain the structural parameters of the fractures in the fracture network, such as fracture length, width, and height, and therefore cannot accurately depict and characterize the fracture network. Summary of the Invention

[0004] The purpose of the present invention is to overcome the problem of inaccurate characterization of fracture networks in the prior art, and to provide a fracture network characterization method, a fracture network characterization device, a machine-readable storage medium and a processor.

[0005] In order to achieve the above-mentioned object, the first aspect of the present invention provides a method for characterizing a fracture network, the method comprising:

[0006] Calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve;

[0007] determining a number of primary fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity;

[0008] establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determining an objective function based on the mathematical model of tracer migration;

[0009] The actual tracer production curve is fitted based on the objective function to obtain a fitted tracer production curve, and the structural parameters of the main fractures in the fracture network are obtained based on the fitted tracer production curve.

[0010] In the embodiment of the present application, the calculation of the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve includes:

[0011] The tracer output concentration at the output outlet is obtained based on the actual tracer output curve;

[0012] The cumulative flow capacity and the cumulative storage capacity of the fracture network are calculated according to the tracer production concentration.

[0013] In an embodiment of the present application, obtaining the tracer output concentration at the output outlet based on the tracer actual output curve includes: optimizing the tracer actual output curve, and obtaining the tracer output concentration at the output outlet based on the optimized tracer actual output curve.

[0014] In the embodiment of the present application, the optimization of the actual output curve of the tracer includes:

[0015] Fitting the curve portion after the peak of the actual tracer output curve to obtain a fitted straight line segment;

[0016] An optimized tracer actual production curve is obtained based on the tracer actual production curve and the fitted straight line segment;

[0017] The fitting straight line segment is shown in the following formula:

[0018] c(t)=be -at (t>t b );

[0019] Where c(t) is the tracer output concentration in mg / L; t is the tracer output time in days; a is the parameter obtained after fitting; b is the parameter obtained after fitting; t b The time corresponding to the start of fitting of the actual tracer output curve, in days.

[0020] In the embodiment of the present application, the cumulative flow capacity of the fracture network is calculated according to the tracer production concentration based on the following formula:

[0021]

[0022] The cumulative storage capacity of the fracture network is calculated based on the tracer production concentration according to the following formula:

[0023]

[0024] In an embodiment of the present application, determining the number of main fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity includes:

[0025] plotting a derivative curve of the cumulative flow capacity and the cumulative storage capacity;

[0026] The number of main fractures in the hydraulic fracture network is determined based on the number of turning points in the derivative curve.

[0027] In the embodiment of the present application, establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network and determining an objective function based on the mathematical model of tracer migration include:

[0028] According to the number of main fractures in the hydraulic fracture network, a tracer migration mathematical model corresponding to each main fracture is established;

[0029] Solving each tracer migration mathematical model to obtain first solution results corresponding to each tracer migration mathematical model, and constructing a tracer theoretical output curve based on each first solution result;

[0030] The tracer theoretical output curve is solved to obtain a second solution result, and an objective function is determined based on the second solution result.

[0031] A second aspect of the present application provides a device for depicting a fracture network, comprising:

[0032] A calculation module is used to calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve;

[0033] a main fracture number determination module, configured to determine the number of main fractures in the hydraulic fracture network based on the cumulative flow capacity and the cumulative storage capacity;

[0034] an objective function determination module, configured to establish a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determine an objective function based on the mathematical model of tracer migration;

[0035] A fitting module is used to fit the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and to obtain structural parameters of main fractures in the fracture network based on the fitted tracer production curve.

[0036] A third aspect of the present application provides a processor configured to execute the above-mentioned fracture network characterization method.

[0037] A fourth aspect of the present application provides a machine-readable storage medium having instructions stored thereon. When the instructions are executed by a processor, the processor is configured to execute the above-mentioned fracture network characterization method.

[0038] The above technical solution includes: calculating the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve; determining the number of main fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity; establishing a tracer migration mathematical model based on the number of main fractures in the fracture network, and determining an objective function based on the tracer migration mathematical model; fitting the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and obtaining the structural parameters of the main fractures in the fracture network based on the fitted tracer production curve. Since the structural parameters of the main fractures in the fracture network can be obtained, the accuracy of the fracture network characterization can be improved.

[0039] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present application but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0041] Figure 1 The following schematically shows a flow chart of a method for characterizing a fracture network according to an embodiment of the present application;

[0042] Figure 2 A schematic diagram schematically illustrates a curve showing a normalized tracer output concentration versus tracer output time according to an embodiment of the present application;

[0043] Figure 3 A schematic diagram illustrating fitting an approximate straight line segment after the peak of the actual output curve of the tracer according to an embodiment of the present application is shown;

[0044] Figure 4 A schematic diagram schematically illustrates a curve showing a cumulative flow capacity versus cumulative storage capacity according to an embodiment of the present application;

[0045] Figure 5 A schematic diagram schematically illustrates a derivative curve of cumulative flow capacity and cumulative storage capacity according to an embodiment of the present application;

[0046] Figure 6 A schematic diagram showing the result of fitting the actual tracer production curve and the actual tracer flowback volume according to an embodiment of the present application is shown;

[0047] Figure 7 Schematically shows a structural block diagram of a fracture network depiction device according to an embodiment of the present application;

[0048] Figure 8 The internal structure diagram of a computer device according to an embodiment of the present application is schematically shown.

[0049] Description of Reference Numerals

[0050] 710 - calculation module; 720 - main crack number determination module; 730 - objective function determination module; 740 - fitting module; A01 - processor; A02 - network interface; A03 - internal memory; A04 - display screen; A05 - input device; A06 - non-volatile storage medium; B01 - operating system; B02 - computer program. DETAILED DESCRIPTION

[0051] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0052] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0053] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0054] As described in the background art, some commonly used methods cannot accurately characterize the fracture network, which is not conducive to the rational formulation of shale oil and gas production system and the optimization of fracturing measures.

[0055] In view of this, an embodiment of the present application provides a method for characterizing a fracture network, such as Figure 1 As shown, the fracture network characterization method may include the following steps:

[0056] Step 101: Calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve.

[0057] The tracer actual production curve is a curve showing the actual production of tracers during oil and gas production. It is a key tool for studying tracer migration in oil and gas systems. By analyzing the tracer actual production curve, it is possible to assess underground reservoir structure and the underground transport of liquids during oil and gas recovery.

[0058] In the embodiment of the present application, step 101 calculates the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve, which may include steps 1 and 2, as follows:

[0059] Step 1: Obtain the tracer output concentration at the output outlet based on the actual tracer output curve.

[0060] The actual tracer production curve can specifically be a curve showing the change of tracer production concentration with tracer production time. Figure 2 The figure below shows the normalized tracer production concentration versus tracer production time for one stage of a multi-stage fractured horizontal well in a domestic shale oil well. In practical applications, the normalized tracer production concentration is calculated by dividing the tracer production concentration by a reference value for comparison and analysis. The reference value can be a baseline value, an initial value, or other pre-selected value. Normalizing the tracer production concentration eliminates the influence of specific concentration values, making tracer production concentration data at different time points comparable and facilitating analysis and research.

[0061] Step 2: Calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the tracer production concentration.

[0062] In the specific implementation of step 2, it can be assumed that after fracturing, n fractures connected to the wellbore are formed, each fracture has a different length, width, and height, and the flow of fluid in the fractures conforms to Darcy's law. Then, the cumulative flow capacity is proportional to the cumulative output mass of the tracer and can be calculated based on the following formula (1); the cumulative storage capacity is proportional to the average residence time of the tracer and can be calculated based on the following formula (2).

[0063]

[0064] Where D(t) is the cumulative storage capacity; c(t) is the tracer output concentration, in mg / L; and t is the tracer output time, in days.

[0065]

[0066] Where M(t) is the cumulative storage capacity in days; c(t) is the tracer output concentration in mg / L; and t is the tracer output time in days.

[0067] In practical applications, to eliminate the influence of the matrix on fracture flow capacity, the actual tracer production curve can be optimized, and the cumulative flow capacity and cumulative storage capacity of the fracture network can be calculated based on the optimized actual tracer production curve. Accordingly, step 1 of obtaining the tracer production concentration at the output outlet based on the actual tracer production curve can include: optimizing the actual tracer production curve, and obtaining the tracer production concentration at the output outlet based on the optimized actual tracer production curve.

[0068] Optimizing the actual tracer production curve may include fitting a portion of the actual tracer production curve after a peak in a semi-logarithmic coordinate system to obtain a fitted straight line segment, such that the fitted straight line segment intersects with the abscissa to form a closed curve. Combining the actual tracer production curve and the fitted straight line segment may yield an optimized actual tracer production curve. Specifically, the front portion of the optimized actual tracer production curve is the actual tracer production curve, and the rear portion is the fitted straight line segment.

[0069] Specifically, fitting the curve portion after the peak value of the actual output curve of the tracer to obtain a fitted straight line segment includes: fitting the approximate straight line segment portion after the peak value of the actual output curve of the tracer to obtain a fitted straight line segment. Figure 3 As shown, the dotted line is the fitted straight line segment obtained after fitting.

[0070] The fitted straight line segment obtained after fitting can be expressed by an exponential function, as shown in the following formula (3):

[0071] c(t)=be -at (t>t b ) (3);

[0072] Where c(t) is the tracer output concentration in mg / L; t is the tracer output time in days; a is the parameter obtained after fitting; b is the parameter obtained after fitting; t b The time corresponding to the start of fitting of the actual tracer output curve, in days.

[0073] catch Figure 3 The example curve in the figure has a fitting straight line segment of y = 2.422e. -0.27x , R 2 = 0.9607; that is, c(t) = 2.422e -0.27t .

[0074] After optimizing the tracer actual production curve to obtain an optimized tracer actual production curve, the cumulative flow capacity and cumulative storage capacity of the fracture network can be calculated based on the tracer production concentration obtained from the optimized tracer actual production curve. Specifically, the cumulative flow capacity can be calculated based on the following formula (4) and the cumulative storage capacity can be calculated based on the following formula (5):

[0075]

[0076]

[0077] Step 102: Determine the number of main fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity.

[0078] The main fractures are the fractures that play a dominant role in seepage and are usually the more prominent and important fractures in the hydraulic fracture network. The key to characterizing the hydraulic fracture network lies in characterizing the main fractures.

[0079] In an embodiment of the present application, determining the number of main fractures in the hydraulic fracture network based on the cumulative flow capacity and the cumulative storage capacity may include: drawing a derivative curve of the cumulative flow capacity and the cumulative storage capacity, and determining the number of main fractures in the hydraulic fracture network based on the number of turning points in the derivative curve.

[0080] In specific implementation, a curve showing the change of cumulative flow capacity with cumulative storage capacity can be drawn with cumulative storage capacity as the horizontal axis and cumulative flow capacity as the vertical axis. Figure 4 As shown, it is a curve of cumulative flow capacity versus cumulative storage capacity, where the cumulative flow capacity and cumulative storage capacity are based on Figure 3 The actual output curve of the optimized tracer is calculated. Then, based on the curve of cumulative flow capacity changing with cumulative storage capacity, the derivative curves of cumulative flow capacity and cumulative storage capacity are drawn. Specifically, the intermediate difference method can be used to calculate dD / dM, and the derivative curve can be drawn in the Cartesian coordinate system. Figure 5 As shown (with Figure 4 Corresponding), it is a derivative curve of cumulative flow capacity and cumulative storage capacity.

[0081] In the above embodiment, determining the number of main cracks in the hydraulic fracture network based on the number of turning points in the derivative curve may include: the number of main cracks in the hydraulic fracture network is (m+1). Wherein, m is the number of turning points in the derivative curve, and m may be an integer ≥ 0. Figure 5 As shown in Figure 5 The presence of a turning point near 0.3 in the middle derivative curve indicates that there are two main fractures in the fracture network.

[0082] Step 103 : establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determining an objective function based on the mathematical model of tracer migration.

[0083] In the embodiment of the present application, a mathematical model of tracer migration is established according to the number of main fractures in the hydraulic fracture network, and an objective function is determined based on the mathematical model of tracer migration. The method may include steps 1, 2, and 3, which are specifically as follows:

[0084] Step 1: According to the number of main fractures in the hydraulic fracture network, a tracer migration mathematical model corresponding to each main fracture is established.

[0085] Specifically, the length of each main crack can be set to L i , width is w i and height h i Based on the number of main fractures in the fracture network, the retention and diffusion effects of the tracer, a mathematical model for tracer injection into each single fracture is established, that is, a mathematical model for tracer migration corresponding to each main fracture.

[0086] Step 2: Solve the mathematical model of each tracer migration to obtain a first solution result, and construct a theoretical tracer output curve based on the first solution result.

[0087] For any mathematical model of tracer migration, the solution process can be as follows: using Laplace transform to obtain the solution related to tracer injection; then, using the mirror reflection principle, obtaining the solution related to tracer flowback; the first solution result includes the solution related to tracer injection and the solution related to tracer flowback.

[0088] In an embodiment of the present application, based on the first solution result, the tracer injection flow rate can be distributed to each fracture according to the seepage resistance of the fracture, and the tracer mass at the production outlet can be mixed to obtain the theoretical tracer production curves of multiple main fractures.

[0089] The theoretical tracer production curves for multiple main fractures can be expressed as follows:

[0090]

[0091] in, is the normalized tracer production concentration; c is the tracer production concentration, in mg / L; c0 is the tracer injection concentration, in mg / L; N is the number of major fractures; V tracer is the tracer injection volume, in m 3 ;L i is the length of the i-th main crack, in meters; W iis the width of the ith main crack, in m; h i is the height of the ith main fracture, in meters; R is the tracer retention coefficient; α i is the tracer diffusion rate in the i-th main fracture, in m; Q inj is the tracer injection flow rate, in m 3 / d (cubic meters / day); t inj is the tracer injection time, in days; Q prod is the tracer flowback flow rate, in m 3 / d (cubic meters / day); t prod is the tracer flowback time, in days.

[0092] Step three: Solve the theoretical tracer output curve to obtain a second solution result, and determine the objective function based on the second solution result.

[0093] In the embodiment of the present application, the objective function can be expressed as the following formula (7):

[0094]

[0095] Where n is the number of main cracks; is the tracer production concentration calculated for the i-th main fracture (it can also be regarded as the tracer production concentration calculated by the i-th tracer migration mathematical model), in mg / L; is the actual output concentration of the tracer, in mg / L; is the tracer flowback volume calculated for the i-th main fracture (it can also be regarded as the tracer flowback volume calculated by the i-th tracer migration mathematical model), in m 3 / d (cubic meters / day); is the actual flowback volume of the tracer, in m 3 / d.

[0096] Step 104 : fitting the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and obtaining structural parameters of main fractures in the hydraulic fracture network based on the fitted tracer production curve.

[0097] In practice, the actual tracer production curve can be fitted using fracture structural parameters (including fracture length, width, and height), tracer retention coefficient, and tracer diffusion rate as fitting parameters, with the objective function as the fitting target. In practical applications, the actual tracer flowback rate can also be fitted while fitting the actual tracer production curve.

[0098] Continuing with the above specific example, relevant parameters are set for the two main fractures, and the tracer cumulative injection volume Qinj t inj 110m 3 The reservoir thickness is 16m. The results of fitting the actual tracer production curve and the actual tracer flowback volume can be shown as follows: Figure 6 As shown. The value of the objective function after fitting is 0.0043. Figure 6 In the figure, curve A is the actual output concentration curve of the tracer, curve B is the output concentration curve of the tracer obtained after fitting, curve C is the actual flowback curve of the tracer, and curve D is the flowback curve of the tracer obtained after fitting.

[0099] After obtaining the fitted tracer production concentration curve and the fitted tracer flowback rate curve, an inversion solution can be performed to obtain the structural parameters of each main fracture in the fracture network, including fracture length, width, and height.

[0100] Continuing with the above example, Figure 6 After inversion and solution of the fitted tracer production concentration curve and the fitted tracer flowback curve, the structural parameters of the two main fractures can be obtained, as shown in Table 1:

[0101] Table 1

[0102]

[0103] It can be understood that the fracture network characterization method provided in the embodiments of the present application includes: calculating the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve; determining the number of main fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity; establishing a tracer migration mathematical model based on the number of main fractures in the fracture network, and determining an objective function based on the tracer migration mathematical model; fitting the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and obtaining the structural parameters of the main fractures in the fracture network based on the fitted tracer production curve. Since the structural parameters of the main fractures in the fracture network can be obtained, the accuracy of the fracture network characterization can be improved.

[0104] On the other hand, the fracture network characterization method provided in the above-mentioned embodiment of the present application can obtain more accurate parameters of each main fracture in the fracture network, reduce the multi-solution, and thus further improve the accuracy of the fracture network characterization.

[0105] Furthermore, existing methods generally interpret and analyze interwell tracers and are not suitable for interpreting fracture parameters during the dual process of tracer injection and flowback in a single well during fracturing. However, the fracture network characterization method provided in the aforementioned embodiments of this application can characterize any single-segment fracture network in a single well, resulting in a more targeted and accurate characterization.

[0106] Figure 1 It should be understood that although Figure 1 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. In addition, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0107] Based on the same inventive concept, Figure 7 As shown, Figure 7 The following schematically illustrates a structural block diagram of a device for characterizing a fracture network according to an embodiment of the present application. In one embodiment, a device for characterizing a fracture network 700 is provided, comprising a calculation module 710, a main fracture number determination module 720, an objective function determination module 730, and a fitting module 740, wherein:

[0108] A calculation module 710 is used to calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve;

[0109] a main fracture number determination module 720 for determining the number of main fractures in the hydraulic fracture network based on the cumulative flow capacity and the cumulative storage capacity;

[0110] An objective function determination module 730 is configured to establish a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determine an objective function based on the mathematical model of tracer migration;

[0111] The fitting module 740 is configured to fit the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and obtain structural parameters of main fractures in the hydraulic fracture network based on the fitted tracer production curve.

[0112] It is understood that the fracture network characterization apparatus provided in the above-described embodiments of the present application can improve the accuracy of fracture network characterization by obtaining the structural parameters of the main fractures within the fracture network. Furthermore, the fracture network characterization apparatus provided in the above-described embodiments of the present application can obtain more accurate parameters of each main fracture within the fracture network, reducing ambiguity and further improving the accuracy of fracture network characterization.

[0113] In one embodiment, the calculation module 710 is used to obtain the tracer output concentration at the output outlet based on the actual tracer output curve;

[0114] The cumulative flow capacity and the cumulative storage capacity of the fracture network are calculated according to the tracer production concentration.

[0115] In one embodiment, the calculation module 710 is used to optimize the actual tracer production curve, and obtain the tracer production concentration at the production outlet based on the optimized actual tracer production curve.

[0116] In one embodiment, the calculation module 710 is used to fit the curve portion after the peak of the actual tracer production curve to obtain a fitted straight line segment;

[0117] An optimized tracer actual production curve is obtained based on the tracer actual production curve and the fitted straight line segment;

[0118] The fitting straight line segment is shown in the following formula:

[0119] c(t)=be -at (t>t b );

[0120] Where c(t) is the tracer output concentration in mg / L; t is the tracer output time in days; a is the parameter obtained after fitting; b is the parameter obtained after fitting; t b The time corresponding to the start of fitting of the actual tracer output curve, in days.

[0121] In one embodiment, the calculation module 710 is configured to calculate the cumulative flow capacity of the fracture network based on the following formula:

[0122]

[0123] The calculation module 710 is used to calculate the cumulative storage capacity of the fracture network based on the following formula:

[0124]

[0125] In one embodiment, the main fracture quantity determination module 720 is configured to plot a derivative curve of the cumulative flow capacity and the cumulative storage capacity;

[0126] The number of main fractures in the hydraulic fracture network is determined based on the number of turning points in the derivative curve.

[0127] In one embodiment, the objective function determination module 730 is configured to establish a tracer migration mathematical model corresponding to each main fracture according to the number of main fractures in the hydraulic fracture network;

[0128] Solving each tracer migration mathematical model to obtain first solution results corresponding to each tracer migration mathematical model, and constructing a tracer theoretical output curve based on each first solution result;

[0129] The tracer theoretical output curve is solved to obtain a second solution result, and an objective function is determined based on the second solution result.

[0130] The calculation module 710, main crack number determination module 720, objective function determination module 730 and fitting module 740 can all be stored in the memory as program units, and the processor executes the program modules stored in the memory to implement corresponding functions.

[0131] The processor contains a core, which retrieves the corresponding program unit from the memory. One or more cores can be configured, and by adjusting the core parameters, rapid fracture network characterization can be achieved at the full chip scale.

[0132] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0133] An embodiment of the present application provides a machine-readable storage medium having a program stored thereon, which implements the above-mentioned method for characterizing a fracture network when executed by a processor.

[0134] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 8 As shown. The computer device includes a processor A01, a network interface A02, a display screen A04, an input device A05 and a memory (not shown in the figure) connected via a system bus. The processor A01 of the computer device is used to provide computing and control capabilities. The memory of the computer device includes an internal memory A03 and a non-volatile storage medium A06. The non-volatile storage medium A06 stores an operating system B01 and a computer program B02. The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 in the non-volatile storage medium A06. The network interface A02 of the computer device is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor A01, a method for characterizing a fracture network is implemented. The display screen A04 of the computer device can be a liquid crystal display or an electronic ink display, and the input device A05 of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad provided on the computer device housing, or an external keyboard, touchpad or mouse.

[0135] Those skilled in the art will understand that Figure 8 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 shown in the figure, or combine certain components, or have a different component arrangement.

[0136] In one embodiment, the fracture network characterization device provided in the present application can be implemented in the form of a computer program. The computer program can be used in Figure 8 The computer device shown in FIG. 1 is run on the computer device shown in FIG. The memory of the computer device can store various program modules that constitute the construction task intelligent scheduling device, such as: Figure 7 The calculation module 710, the main fracture number determination module 720, the objective function determination module 730 and the fitting module 740 are shown. The computer program composed of various program modules enables the processor to execute the steps of the fracture network characterization method of each embodiment of the present application described in this specification.

[0137] Figure 8 The computer device shown can be Figure 7 The calculation module 710, the main fracture number determination module 720, the objective function determination module 730 and the fitting module 740 in the fracture network characterization device are shown to execute the method.

[0138] An embodiment of the present application provides a device, comprising a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the following steps are performed:

[0139] Calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve;

[0140] determining a number of primary fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity;

[0141] establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determining an objective function based on the mathematical model of tracer migration;

[0142] The actual tracer production curve is fitted based on the objective function to obtain a fitted tracer production curve, and the structural parameters of the main fractures in the fracture network are obtained based on the fitted tracer production curve.

[0143] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0144] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0145] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0146] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0147] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0148] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0149] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology for information storage. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media such as modulated data signals and carrier waves.

[0150] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0151] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A method for depicting a fracture network, characterized in that: include: Calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve; determining a number of primary fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity; establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determining an objective function based on the mathematical model of tracer migration; The actual tracer production curve is fitted based on the objective function to obtain a fitted tracer production curve, and the structural parameters of the main fractures in the fracture network are obtained based on the fitted tracer production curve.

2. The method for depicting a fracture network according to claim 1, wherein: The calculation of the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve includes: The tracer output concentration at the output outlet is obtained based on the actual tracer output curve; The cumulative flow capacity and the cumulative storage capacity of the fracture network are calculated according to the tracer production concentration.

3. The method for depicting a fracture network according to claim 2, wherein: The obtaining of the tracer output concentration at the output outlet based on the actual tracer output curve includes: optimizing the actual tracer output curve, and obtaining the tracer output concentration at the output outlet based on the optimized actual tracer output curve.

4. The method for depicting a fracture network according to claim 3, wherein: The optimization of the actual output curve of the tracer includes: Fitting the curve portion after the peak of the actual tracer output curve to obtain a fitted straight line segment; An optimized tracer actual production curve is obtained based on the tracer actual production curve and the fitted straight line segment; The fitting straight line segment is shown in the following formula: c(t)=be -at (t>t b ); Where c(t) is the tracer output concentration in mg / L; t is the tracer output time in days; a is the parameter obtained after fitting; b is the parameter obtained after fitting; t b The time corresponding to the start of fitting of the actual tracer output curve, in days.

5. The method for depicting a fracture network according to claim 4, wherein: The cumulative flow capacity of the fracture network is calculated based on the tracer production concentration according to the following formula: The cumulative storage capacity of the fracture network is calculated based on the tracer production concentration according to the following formula:

6. The method for depicting a fracture network according to claim 1, wherein: Determining the number of main fractures in the fracture network based on the cumulative flow capacity and the cumulative storage capacity includes: plotting a derivative curve of the cumulative flow capacity and the cumulative storage capacity; The number of main fractures in the hydraulic fracture network is determined based on the number of turning points in the derivative curve.

7. The method for depicting a fracture network according to claim 1, wherein: The method of establishing a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network and determining an objective function based on the mathematical model of tracer migration includes: According to the number of main fractures in the hydraulic fracture network, a tracer migration mathematical model corresponding to each main fracture is established; Solving each tracer migration mathematical model to obtain first solution results corresponding to each tracer migration mathematical model, and constructing a tracer theoretical output curve based on each first solution result; The tracer theoretical output curve is solved to obtain a second solution result, and an objective function is determined based on the second solution result.

8. A device for depicting a fracture network, characterized in that: include: A calculation module is used to calculate the cumulative flow capacity and cumulative storage capacity of the fracture network based on the actual tracer production curve; a main fracture number determination module, configured to determine the number of main fractures in the hydraulic fracture network based on the cumulative flow capacity and the cumulative storage capacity; an objective function determination module, configured to establish a mathematical model of tracer migration according to the number of main fractures in the hydraulic fracture network, and determine an objective function based on the mathematical model of tracer migration; A fitting module is used to fit the actual tracer production curve based on the objective function to obtain a fitted tracer production curve, and to obtain structural parameters of main fractures in the fracture network based on the fitted tracer production curve.

9. A processor, characterized in that: The method is configured to perform the fracture network characterization method according to any one of claims 1 to 7.

10. A machine-readable storage medium having instructions stored thereon, characterized in that: When the instruction is executed by a processor, the processor is configured to perform the fracture network characterization method according to any one of claims 1 to 7.

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