Carbonate reservoir crack identification method

Abstract

The invention provides a carbonate reservoir crack identification method. The method comprises the steps that logging data of a carbonate reservoir to be identified are acquired, and the logging data comprise total porosity data and density logging value data; generating a total porosity curve based on the total porosity data; generating a density logging value curve based on the density logging value data; overlapping the total porosity curve and the density logging value curve so as to obtain a curve overlapping graph after the overlap ratio of the total porosity curve and the density logging value curve is greater than a preset overlap ratio threshold value; according to the density logging value curve, determining a potential fracture development zone; in the curve overlapping graph, determining a potential curve overlapping graph corresponding to the potential fracture-developed zone; determining a target fracture-developed zone according to the potential curve overlapping graph; the method is used for achieving the effect of improving the carbonate reservoir crack recognition efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas field exploration and development, and in particular to a method for identifying fractures in carbonate reservoirs. Background Art

[0002] With the continuous advancement of science and technology, oil and gas field exploration and development has become the core project of current development. Among them, carbonate rocks are rich in oil and gas resources and are the top priority of oil and gas field exploration and development. Carbonate reservoirs often develop cracks. These cracks are not only important storage spaces, but also can significantly increase permeability. Therefore, identifying carbonate reservoir cracks is crucial to oil and gas exploration and development.

[0003] In the existing technology, the identification method of carbonate reservoir fractures is mainly achieved through petrological observation, physical property data analysis and logging data interpretation.

[0004] However, due to the influence of reservoir heterogeneity and uneven fracture development, existing methods and technologies are costly and time-consuming in fracture identification, and the fracture identification results are multi-solution and limited, resulting in low efficiency of fracture identification in carbonate reservoirs. Summary of the Invention

[0005] The embodiment of the present application provides a method for identifying fractures in carbonate reservoirs, so as to improve the efficiency of identifying fractures in carbonate reservoirs.

[0006] In a first aspect, an embodiment of the present application provides a method for identifying fractures in a carbonate reservoir, comprising:

[0007] Acquiring well logging data of the carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data;

[0008] Based on the total porosity data, a total porosity curve is generated;

[0009] Generate a density logging value curve based on density logging value data;

[0010] Overlapping the total porosity curve and the density logging value curve to obtain a curve overlap graph when the overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold;

[0011] According to the density logging value curve, the potential fracture development zone is determined;

[0012] In the curve overlap diagram, determine the potential curve overlap diagram corresponding to the potential fracture development zone;

[0013] Determine the target fracture development zone based on the potential curve overlap diagram.

[0014] In one possible implementation, determining a potential fracture development zone based on a density logging value curve includes:

[0015] On the density logging value curve, determine the high density logging value baseline;

[0016] The carbonate reservoir corresponding to the density logging value lower than the high-density logging value baseline is identified as the potential fracture development zone.

[0017] In one possible implementation, determining a target fracture development zone based on a potential curve overlap diagram includes:

[0018] Determine the overlapping area and non-overlapping area of the total porosity curve and the density log value curve in the potential curve overlap diagram;

[0019] Calculating interval values for separate intervals of the total porosity curve and the density log value curve in non-overlapping areas;

[0020] If the interval value corresponding to the non-overlapping area is greater than the preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined to be the target fracture development zone.

[0021] In a possible implementation, if the interval value corresponding to the non-overlapping area is greater than a preset interval threshold, then after determining that the carbonate reservoir corresponding to the non-overlapping area is a target fracture development zone, the method further includes:

[0022] The development degree of the target fracture development zone is determined according to the interval value of the separation interval of the total porosity curve and the density logging value curve corresponding to the target fracture development zone.

[0023] In a possible implementation, the method for identifying carbonate reservoir fractures further includes:

[0024] Obtaining basic geological data of the carbonate reservoir to be identified, wherein the basic geological data includes at least one of drilling and outcrop horizon information, regional tectonic background, sedimentary environment, and burial history;

[0025] Collect downhole core and field outcrop samples based on basic geological data;

[0026] Conducting petrological observations on downhole cores and field outcrop samples to determine characteristic information of the carbonate reservoir to be identified, wherein the characteristic information includes at least one of the following: fracture development type, whether it is open or closed, the number of fractures developed, and whether the fractures are filled;

[0027] Based on the characteristic information of the carbonate reservoir to be identified, the correctness of the target fracture development zone is verified.

[0028] In a possible implementation, the method for identifying carbonate reservoir fractures further includes:

[0029] obtaining multiple core samples of the carbonate reservoir to be identified;

[0030] Performing pre-experimental processing on multiple core samples to obtain multiple samples to be measured;

[0031] Determine the porosity and permeability of the sample to be measured;

[0032] Generate a porosity and permeability intersection diagram based on porosity and permeability;

[0033] The correctness of the target fracture development zone is verified based on the porosity and permeability intersection diagram.

[0034] In a second aspect, an embodiment of the present application provides a device for identifying fractures in a carbonate reservoir, comprising:

[0035] An acquisition module is used to acquire well logging data of the carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data;

[0036] A first curve generating module is used to generate a total porosity curve based on the total porosity data;

[0037] A second curve generating module is used to generate a density logging value curve based on the density logging value data;

[0038] an overlap processing module for overlapping the total porosity curve and the density logging value curve to obtain a curve overlap graph when the overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold;

[0039] The first determination module is used to determine the potential fracture development zone based on the density logging value curve;

[0040] The second determining module is used to determine the potential curve overlap map corresponding to the potential fracture development zone in the curve overlap map;

[0041] The third determination module is used to determine the target fracture development zone based on the potential curve overlap map.

[0042] In a possible implementation, the first determining module is further configured to:

[0043] On the density logging value curve, determine the high density logging value baseline;

[0044] The carbonate reservoir corresponding to the density logging value lower than the high-density logging value baseline is identified as the potential fracture development zone.

[0045] In a possible implementation, the third determining module is further configured to:

[0046] Determine the overlapping area and non-overlapping area of the total porosity curve and the density log value curve in the potential curve overlap diagram;

[0047] Calculating interval values for separate intervals of the total porosity curve and the density log value curve in non-overlapping areas;

[0048] If the interval value corresponding to the non-overlapping area is greater than the preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined to be the target fracture development zone.

[0049] In a possible implementation, the third determining module is further configured to:

[0050] The development degree of the target fracture development zone is determined according to the interval value of the separation interval of the total porosity curve and the density logging value curve corresponding to the target fracture development zone.

[0051] In a possible implementation, the third determining module is further configured to:

[0052] Obtaining basic geological data of the carbonate reservoir to be identified, wherein the basic geological data includes at least one of drilling and outcrop horizon information, regional tectonic background, sedimentary environment, and burial history;

[0053] Collect downhole core and field outcrop samples based on basic geological data;

[0054] Conducting petrological observations on downhole cores and field outcrop samples to determine characteristic information of the carbonate reservoir to be identified, wherein the characteristic information includes at least one of the following: fracture development type, whether it is open or closed, the number of fractures developed, and whether the fractures are filled;

[0055] Based on the characteristic information of the carbonate reservoir to be identified, the correctness of the target fracture development zone is verified.

[0056] In a possible implementation, the third determining module is further configured to:

[0057] obtaining multiple core samples of the carbonate reservoir to be identified;

[0058] Performing pre-experimental processing on multiple core samples to obtain multiple samples to be measured;

[0059] Determine the porosity and permeability of the sample to be measured;

[0060] Generate a porosity and permeability intersection diagram based on porosity and permeability;

[0061] The correctness of the target fracture development zone is verified based on the porosity and permeability intersection diagram.

[0062] In a third aspect, an embodiment of the present application provides a device for identifying fractures in a carbonate reservoir, comprising: a memory, a processor;

[0063] Memory stores computer-executable instructions;

[0064] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above first aspect and / or various possible implementations of the first aspect.

[0065] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementation methods of the first aspect.

[0066] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above first aspect and / or various possible implementation methods of the first aspect.

[0067] The present application provides a method for identifying fractures in carbonate reservoirs. The method comprises the following steps: obtaining logging data including total porosity data and density logging value data in a carbonate reservoir to be identified, and generating a total porosity curve based on the total porosity data and a density logging value curve based on the density logging value data; then, overlapping the total porosity curve and the density logging value curve is performed to obtain a curve overlap graph when the degree of overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold; then, determining a potential fracture development zone based on the density logging value curve; and further determining the potential fracture development zone in the curve overlap graph. The potential curve overlap map corresponding to the zone is obtained; finally, the target fracture development zone is determined according to the potential curve overlap map, thereby providing a solid foundation for subsequent fracture identification by obtaining the logging data to be identified, ensuring the reliability of the subsequent carbonate reservoir identification results. In addition, the potential fracture development zone is determined based on the density logging value, and the fracture development zone is determined according to the curve overlap map. While reducing the development cost, the convenience and speed of the identification process are improved. Furthermore, the position of the fracture development zone is determined through the relationship between total porosity logging and density logging, which improves the identification accuracy and achieves the effect of improving the efficiency of carbonate reservoir fracture identification. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0069] Figure 1 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 1 ;

[0070] Figure 2 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 2 ;

[0071] Figure 3 A schematic diagram of comprehensive well logging provided in an embodiment of the present application;

[0072] Figure 4 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 3 ;

[0073] Figure 5 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 4 ;

[0074] Figure 6 A porosity and permeability intersection diagram of a carbonate reservoir to be identified provided in an embodiment of the present application;

[0075] Figure 7 A schematic diagram of the structure of a carbonate reservoir fracture identification device provided in an embodiment of the present application;

[0076] Figure 8 A schematic diagram of the structure of a carbonate reservoir fracture identification device provided in an embodiment of the present application.

[0077] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0078] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0079] Due to the influence of reservoir heterogeneity and uneven fracture development, existing methods and technologies for fracture identification are costly and time-consuming, and the fracture identification results are multi-solution and limited, resulting in low efficiency of fracture identification in carbonate reservoirs.

[0080] A method for identifying carbonate reservoir fractures provided in an embodiment of the present application provides a solid foundation for subsequent fracture identification by acquiring logging data to be identified, thereby ensuring the reliability of subsequent carbonate reservoir identification results. In addition, potential fracture development zones are determined based on density logging values, and fracture development zones are determined based on curve overlap graphs. This reduces development costs while improving the convenience and speed of the identification process. Furthermore, the location of the fracture development zone is determined based on the relationship between total porosity logging and density logging, thereby improving identification accuracy and achieving the effect of improving the efficiency of carbonate reservoir fracture identification.

[0081] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0082] Figure 1 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 1 ,like Figure 1 As shown, the method includes:

[0083] S101, obtaining well logging data of a carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data;

[0084] In this embodiment, the logging data refers to data on physical properties of underground rocks measured by a logging instrument in a well, including but not limited to density porosity, total porosity, resistivity and / or density.

[0085] Obtain total porosity data and density logging data of the carbonate reservoir to be identified in the target area.

[0086] S102. Generate a total porosity curve based on the total porosity data;

[0087] In this embodiment, the total porosity curve is a graph showing the total porosity of rock changing with well depth, wherein the vertical axis of the curve represents the position of the logging instrument in the well, that is, the well depth, and the horizontal axis represents the total porosity.

[0088] The total porosity data obtained are sorted by well depth and plotted into a graph to generate a total porosity curve to determine the changes in porosity in the reservoir.

[0089] S103, generating a density logging value curve based on the density logging value data;

[0090] In this embodiment, the density logging value curve is a graph showing formation density and porosity changing with depth, wherein the vertical axis of the curve represents the position of the logging instrument in the well, i.e., the well depth, and the horizontal axis represents the density value of the formation.

[0091] Similarly, the acquired density logging value data are sorted according to the well depth and plotted into a graph to generate a density logging value curve to determine the change in rock density in the reservoir.

[0092] S104, performing an overlapping process on the total porosity curve and the density logging value curve, so as to obtain a curve overlapping graph after the overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold;

[0093] In this embodiment, the method for overlapping the total porosity curve and the density logging value curve is a curve overlapping method, wherein the curve overlapping method refers to a processing method for superimposing and displaying at least two logging curves on the same graph at the same depth ratio.

[0094] The total porosity curve and the density logging value curve are overlapped in the same coordinate system to observe the coincidence of the two curves. By adjusting the interval range, the coincidence of the two curves is ensured to be greater than the preset coincidence threshold to obtain the corresponding curve overlap diagram.

[0095] S105. Determine potential fracture development zones based on the density logging value curve;

[0096] On the density logging value curve, since the presence of cracks will reduce the density of the rock, the area with lower density logging values in the density logging value curve is determined as the potential fracture development zone.

[0097] S106. Determine, in the curve overlap graph, a potential curve overlap graph corresponding to the potential fracture development zone;

[0098] In the curve overlap diagram, find the area corresponding to the potential fracture development zone and observe the overlap of the total porosity curve and the density logging value curve in this area. If the two curves do not overlap in this area and there is a large separation interval, the curve overlap diagram corresponding to this area is determined as the potential curve overlap diagram.

[0099] S107. Determine the target fracture development zone based on the potential curve overlap diagram.

[0100] Based on the potential curve overlap map obtained above, the target fracture development zone of the carbonate rock is further determined.

[0101] The present application provides a method for identifying fractures in carbonate reservoirs. The method comprises the following steps: obtaining logging data including total porosity data and density logging value data in a carbonate reservoir to be identified, and generating a total porosity curve based on the total porosity data and a density logging value curve based on the density logging value data; then, overlapping the total porosity curve and the density logging value curve is performed to obtain a curve overlap graph when the degree of overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold; then, determining a potential fracture development zone based on the density logging value curve; and further determining the potential fracture development zone in the curve overlap graph. The potential curve overlap map corresponding to the zone is obtained; finally, the target fracture development zone is determined according to the potential curve overlap map, thereby providing a solid foundation for subsequent fracture identification by obtaining the logging data to be identified, ensuring the reliability of the subsequent carbonate reservoir identification results. In addition, the potential fracture development zone is determined based on the density logging value, and the fracture development zone is determined according to the curve overlap map. While reducing the development cost, the convenience and speed of the identification process are improved. Furthermore, the position of the fracture development zone is determined through the relationship between total porosity logging and density logging, which improves the identification accuracy and achieves the effect of improving the efficiency of carbonate reservoir fracture identification.

[0102] Figure 2 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 2 ,like Figure 2 As shown, this embodiment, based on the above embodiment, describes in detail the process of obtaining potential fracture development zones and target fracture development zones. The method includes:

[0103] S201. Determine a high-density logging value baseline on a density logging value curve;

[0104] In this embodiment, the high-density logging value baseline represents a relatively high density value in the formation. The high-density logging value baseline is a settable threshold that can be determined based on actual conditions and is not specifically limited in this embodiment of the present application.

[0105] Optionally, on the density logging value curve, a high-density logging value baseline is determined based on historical data, user requirements, or image screening.

[0106] S202, determining the carbonate reservoir corresponding to the density logging value lower than the high-density logging value baseline as a potential fracture development zone;

[0107] Since fractures and pores can reduce the density of the formation, carbonate reservoirs with density logging values lower than the high-density logging value baseline are identified as potential fracture development zones.

[0108] S203. Determine a potential curve overlap map corresponding to a potential fracture development zone in the curve overlap map;

[0109] The portion corresponding to the potential fracture development zone is found in the curve overlap diagram and is determined as the potential curve overlap diagram.

[0110] S204, determining the overlapping area and non-overlapping area of the total porosity curve and the density logging value curve in the potential curve overlap map;

[0111] In this embodiment, the overlapping area indicates that the two curves have similar characteristics at the same stratum depth, and the non-overlapping area indicates that the two curves have different characteristics at the same stratum depth.

[0112] In the potential curve overlap map, the overlapping portion of the total porosity curve and the density logging value curve is determined as the overlapping area, and the non-overlapping portion of the total porosity curve and the density logging value curve is determined as the non-overlapping area.

[0113] S205, calculating the interval values of the separated intervals of the total porosity curve and the density logging value curve in the non-overlapping area;

[0114] In this embodiment, the interval value of the separated interval is used to indicate the difference or distance between the total porosity curve and the density logging value curve in the non-overlapping area. The size of the interval value represents the degree of fracture development or the complexity of the formation. The interval value is positively correlated with the degree of fracture development or the complexity of the formation, that is, the larger the interval value, the higher the degree of fracture development or the complexity of the formation.

[0115] By numerical comparison, the difference or distance between the total porosity curve and the density log value curve in the non-overlapping area is calculated.

[0116] S206: If the interval value corresponding to the non-overlapping area is greater than the preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined to be the target fracture development zone;

[0117] When the interval value corresponding to the non-overlapping area is greater than the preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined as the target fracture development zone.

[0118] Specifically, Figure 3 The comprehensive logging diagram provided in the embodiment of this application is as follows: Figure 3 As shown in the figure, the area within the blue frame represents the non-fracture section, the part marked in orange and marked with Fx represents the fracture section, and Fracture represents the fracture location, where x represents any number from 1 to 7. On the comprehensive logging map, 7 intervals with low-density logging and where the density logging curve does not overlap with the total porosity logging curve are identified and defined as fracture development sections.

[0119] It is understandable that Figure 3The results are only presented for illustrative purposes and do not affect the scope of protection of the embodiments of the present application.

[0120] S207 : Determine the development degree of the target fracture development zone according to the interval values of the separation intervals of the total porosity curve and the density logging value curve corresponding to the target fracture development zone.

[0121] The interval value of the separation interval of the total porosity curve and the density logging value curve corresponding to the target fracture development zone is obtained. If the value is larger, the development degree of the target fracture development zone is higher; otherwise, the development degree of the target fracture development zone is lower.

[0122] Optionally, after determining the target fracture development zone, a visualization process is performed on the position corresponding to the target fracture development zone, wherein the visualization process includes but is not limited to a labeling process.

[0123] The present invention provides a method for identifying fractures in carbonate reservoirs. By analyzing density logging curves, a high-density logging baseline is first determined. Based on this, carbonate reservoirs corresponding to density logging values below this baseline are identified as potential fracture zones. Next, the image corresponding to the potential fracture zones is located in a curve overlap plot, and the overlapping and non-overlapping regions of the total porosity curve and the density logging curve are distinguished. Furthermore, the interval value separating the two curves in the non-overlapping region is calculated. When this interval value exceeds a preset interval threshold, the corresponding carbonate reservoir is identified as a target fracture zone. Finally, based on the interval value corresponding to the target fracture zone, the development level of the fracture zone is assessed. Thus, the target fracture zone is determined using the two curves, significantly reducing the development costs associated with fracture identification. Furthermore, determining the target fracture zone corresponding to the carbonate reservoir based on the numerical value of the interval value not only improves the convenience and speed of the identification process, but also improves the accuracy and reliability of fracture identification, thereby increasing the efficiency of fracture identification in carbonate reservoirs.

[0124] Figure 4 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 3 ,like Figure 4 As shown, this embodiment, based on the above embodiment, describes in detail the verification process of the target fracture development zone, and the method includes:

[0125] S401. Obtain basic geological data of the carbonate reservoir to be identified;

[0126] In this embodiment, the basic geological data includes at least one of drilling and outcrop layer information, regional tectonic background, sedimentary environment and burial history.

[0127] Specifically, taking the dolomite section of the Alamein Formation of the Cretaceous System in Site A as an example, based on the research scope, basic geological data of Site A including drilling and outcrop stratigraphic information, regional tectonic background and sedimentary environment, and burial history were compiled.

[0128] S402. Collect downhole core and field outcrop samples based on basic geological data;

[0129] Specifically, based on the collated basic geological data of Site A, downhole cores of the Alamein Formation from three wells were selected for density sampling, and field outcrop samples were collected.

[0130] S403, conducting petrological observations on downhole cores and field outcrop samples to determine characteristic information of the carbonate reservoir to be identified;

[0131] In this embodiment, the characteristic information includes at least one of the type of fracture development, whether it is open or closed, the number of fractures developed, and whether the fractures are filled.

[0132] Specifically, detailed petrological observations were conducted on the downhole cores and field outcrop samples collected at Site A, and the characteristics of each sample, such as the type of fracture development (high-angle, medium-angle, or low-angle fractures), whether they were open or closed, the number of fractures developed, and whether the fractures were filled, were counted.

[0133] S404. Verify the correctness of the target fracture development zone based on the characteristic information of the carbonate reservoir to be identified.

[0134] Specifically, the correctness of the target fracture development zone is verified based on the degree of consistency between the characteristic information of the carbonate reservoir to be identified in site A and the known information.

[0135] An embodiment of the present application provides a method for identifying fractures in carbonate reservoirs. The method obtains basic geological data of the carbonate reservoir to be identified, collects downhole core and field outcrop samples, conducts petrological observations to determine characteristic information, and verifies the correctness of the target fracture development zone based on the characteristic information. The target fracture development zone is verified using the characteristic information, thereby ensuring the accuracy and reliability of the fracture identification results, reducing the time cost of the identification process, and achieving the effect of improving the efficiency of carbonate reservoir fracture identification.

[0136] Figure 5 A schematic diagram of a method for identifying fractures in carbonate reservoirs provided in an embodiment of the present application Figure 4 ,like Figure 5 As shown, this embodiment, based on the above embodiment, describes in detail the verification process of the target fracture development zone, and the method includes:

[0137] S501, obtaining multiple core samples of the carbonate reservoir to be identified;

[0138] Specifically, multiple core samples were selected and plunger rock samples with a diameter of 1 inch were drilled.

[0139] S502, performing pre-experimental processing on a plurality of core samples to obtain a plurality of samples to be measured;

[0140] Specifically, the rock samples are washed with oil one by one and then dried to obtain a plurality of samples to be measured.

[0141] S503, measuring the porosity and permeability of the sample to be measured;

[0142] After ensuring that all samples to be measured have been dried, the porosity and permeability of the samples to be measured are measured.

[0143] S504, generating a porosity and permeability intersection map based on the porosity and permeability;

[0144] Specifically, Figure 6 The porosity and permeability intersection diagram of the carbonate reservoir to be identified provided in the embodiment of the present application is as follows: Figure 6 As shown in the figure, a porosity and permeability intersection diagram is generated based on porosity and permeability. Among them, the permeability coordinate system uses logarithmic coordinates. When the porosity remains unchanged, the abnormally large permeability value often corresponds to the fracture development zone. Taking the single well in site A as an example, on the porosity and permeability intersection diagram, the abnormally high permeability value indicates the fracture development section.

[0145] It is understandable that Figure 6 The results are only presented for illustrative purposes and do not affect the scope of protection of the embodiments of the present application.

[0146] S505. Verify the correctness of the target fracture development zone based on the porosity and permeability intersection diagram.

[0147] Specifically, the distribution of porosity and permeability data points for different rock types or fracture zones on the intersection diagram, as well as whether these data points form specific trends or patterns, can be used to determine the accuracy of the prediction of the target fracture zone. If the data points on the intersection diagram match the characteristics of the predicted fracture zone, for example, compared to the typical positive correlation between porosity and permeability, the permeability significantly increases relative to the porosity, then the prediction of the target fracture zone can be considered correct.

[0148] An embodiment of the present application provides a method for identifying fractures in carbonate reservoirs. The method obtains multiple core samples from the carbonate reservoir to be identified, performs experimental pre-processing to obtain the samples to be measured, measures their porosity and permeability, generates a porosity and permeability intersection diagram, and verifies the correctness of the target fracture development zone based on the intersection diagram. This ensures the accuracy and reliability of the fracture identification results, reduces the time cost of the identification process, and achieves the effect of improving the efficiency of carbonate reservoir fracture identification.

[0149] Figure 7 This is a schematic diagram of the structure of a carbonate reservoir fracture identification device provided in an embodiment of the present application. The device of this embodiment can be in the form of software and / or hardware. Figure 7 As shown, the carbonate reservoir fracture identification device 700 provided in an embodiment of the present application includes: an acquisition module 701, a first curve generation module 702, a second curve generation module 703, an overlap processing module 704, a first determination module 705, a second determination module 706, and a third determination module 707:

[0150] An acquisition module 701 is used to acquire well logging data of the carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data;

[0151] A first curve generating module 702 is configured to generate a total porosity curve based on the total porosity data;

[0152] The second curve generating module 703 is used to generate a density logging value curve based on the density logging value data;

[0153] The overlap processing module 704 is used to overlap the total porosity curve and the density logging value curve to obtain a curve overlap graph after the overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold;

[0154] The first determination module 705 is used to determine the potential fracture development zone based on the density logging value curve;

[0155] The second determining module 706 is configured to determine a potential curve overlap map corresponding to a potential fracture development zone in the curve overlap map;

[0156] The third determination module 707 is used to determine the target fracture development zone according to the potential curve overlap map.

[0157] In a possible implementation, the first determining module 705 is further configured to:

[0158] On the density logging value curve, determine the high density logging value baseline;

[0159] The carbonate reservoir corresponding to the density logging value lower than the high-density logging value baseline is identified as the potential fracture development zone.

[0160] In a possible implementation, the third determining module 707 is further configured to:

[0161] Determine the overlapping area and non-overlapping area of the total porosity curve and the density log value curve in the potential curve overlap diagram;

[0162] Calculating interval values for separate intervals of the total porosity curve and the density log value curve in non-overlapping areas;

[0163] If the interval value corresponding to the non-overlapping area is greater than the preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined to be the target fracture development zone.

[0164] In a possible implementation, the third determining module 707 is further configured to:

[0165] The development degree of the target fracture development zone is determined according to the interval value of the separation interval of the total porosity curve and the density logging value curve corresponding to the target fracture development zone.

[0166] In a possible implementation, the third determining module 707 is further configured to:

[0167] Obtaining basic geological data of the carbonate reservoir to be identified, wherein the basic geological data includes at least one of drilling and outcrop horizon information, regional tectonic background, sedimentary environment, and burial history;

[0168] Collect downhole core and field outcrop samples based on basic geological data;

[0169] Conducting petrological observations on downhole cores and field outcrop samples to determine characteristic information of the carbonate reservoir to be identified, wherein the characteristic information includes at least one of the following: fracture development type, whether it is open or closed, the number of fractures developed, and whether the fractures are filled;

[0170] Based on the characteristic information of the carbonate reservoir to be identified, the correctness of the target fracture development zone is verified.

[0171] In a possible implementation, the third determining module 707 is further configured to:

[0172] obtaining multiple core samples of the carbonate reservoir to be identified;

[0173] Performing pre-experimental processing on multiple core samples to obtain multiple samples to be measured;

[0174] Determine the porosity and permeability of the sample to be measured;

[0175] Generate a porosity and permeability intersection diagram based on porosity and permeability;

[0176] The correctness of the target fracture development zone is verified based on the porosity and permeability intersection diagram.

[0177] The present embodiment provides a device for identifying fractures in carbonate reservoirs, which can execute the method provided in the above method embodiment. The implementation principle and technical effects thereof are similar, and are not described in detail in this embodiment.

[0178] Figure 8 This is a schematic diagram of the structure of a carbonate reservoir fracture identification device provided in an embodiment of the present application. Figure 8 As shown, the electronic device 800 provided in this embodiment includes: at least one processor 801 and a memory 802. Optionally, the device 800 also includes a communication component 803. The processor 801, the memory 802 and the communication component 803 are connected via a bus.

[0179] During the specific implementation process, at least one processor 801 executes the computer-executable instructions stored in the memory 802, so that the at least one processor 801 performs the above method.

[0180] The specific implementation process of the processor 801 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0181] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASICs), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules within the processor.

[0182] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage.

[0183] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0184] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0185] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0186] The readable storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0187] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0188] The division of units is merely a logical functional division; actual implementations may employ alternative divisions, such as combining or integrating multiple units or components into another system, or omitting or disabling certain features. Furthermore, any direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units, either through an interface, electrical, mechanical, or other means.

[0189] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0190] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0191] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0192] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0193] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A method for identifying fractures in carbonate reservoirs, characterized in that: include: Acquiring well logging data of the carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data; generating a total porosity curve based on the total porosity data; generating a density logging value curve based on the density logging value data; Overlapping the total porosity curve and the density logging value curve to obtain a curve overlap graph when the degree of overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold; determining a potential fracture development zone based on the density logging value curve; Determining a potential curve overlap map corresponding to the potential fracture development zone in the curve overlap map; The target fracture development zone is determined based on the potential curve overlap diagram.

2. The method according to claim 1, characterized in that Determining the potential fracture development zone based on the density logging value curve includes: Determining a high-density logging value baseline on the density logging value curve; The carbonate reservoir corresponding to the density logging value lower than the high-density logging value baseline is determined as a potential fracture development zone.

3. The method according to claim 2, characterized in that Determining the target fracture development zone according to the potential curve overlap map includes: Determine, in the potential curve overlap graph, overlapping areas and non-overlapping areas of the total porosity curve and the density logging value curve; Calculating interval values of separate intervals of the total porosity curve and the density log value curve in the non-overlapping area; If the interval value corresponding to the non-overlapping area is greater than a preset interval threshold, the carbonate reservoir corresponding to the non-overlapping area is determined to be the target fracture development zone.

4. The method according to claim 3, characterized in that After determining that the carbonate reservoir corresponding to the non-overlapping area is a target fracture development zone if the interval value corresponding to the non-overlapping area is greater than a preset interval threshold, the method further includes: The development degree of the target fracture development zone is determined according to the interval value of the separation interval of the total porosity curve and the density logging value curve corresponding to the target fracture development zone.

5. The method according to any one of claims 1 to 4, characterized in that Also includes: Obtaining basic geological data of the carbonate reservoir to be identified, wherein the basic geological data includes at least one of drilling and outcrop horizon information, regional tectonic background, sedimentary environment, and burial history; Collect downhole core and field outcrop samples based on the basic geological data; Performing petrological observations on the downhole cores and field outcrop samples to determine characteristic information of the carbonate reservoir to be identified, wherein the characteristic information includes at least one of the type of fracture development, whether it is open or closed, the number of fractures developed, and whether the fractures are filled; The correctness of the target fracture development zone is verified based on the characteristic information of the carbonate reservoir to be identified.

6. The method according to any one of claims 1 to 4, characterized in that Also includes: Obtaining a plurality of core samples of the carbonate reservoir to be identified; performing pre-experimental processing on the plurality of core samples to obtain a plurality of samples to be measured; Determining the porosity and permeability of the sample to be measured; generating a porosity and permeability intersection map based on the porosity and permeability; The correctness of the target fracture development zone is verified based on the porosity and permeability intersection diagram.

7. A device for identifying fractures in carbonate reservoirs, characterized in that: include: An acquisition module, configured to acquire well logging data of the carbonate reservoir to be identified, wherein the well logging data includes total porosity data and density logging value data; A first curve generating module, configured to generate a total porosity curve based on the total porosity data; A second curve generating module is used to generate a density logging value curve based on the density logging value data; an overlap processing module, configured to perform overlap processing on the total porosity curve and the density logging value curve, so as to obtain a curve overlap graph after the overlap between the total porosity curve and the density logging value curve is greater than a preset overlap threshold; A first determination module is used to determine a potential fracture development zone based on the density logging value curve; A second determining module is configured to determine, in the curve overlap graph, a potential curve overlap graph corresponding to the potential fracture development zone; The third determination module is used to determine the target fracture development zone according to the potential curve overlap map.

8. A device for identifying fractures in carbonate reservoirs, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method for identifying carbonate reservoir fractures according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method for identifying carbonate reservoir fractures according to any one of claims 1 to 7.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method for identifying carbonate reservoir fractures according to any one of claims 1 to 7 is implemented.

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