Method and system for representing development and distribution characteristics of karst fractures and caves

Abstract

The invention discloses a method and system for representing development and distribution characteristics of karst fractures and caves. The method comprises the following steps: collecting single-well primary produced fluid of each well in a work area to be evaluated; according to the range of the data values, dividing the data range of the primary produced fluid of the single well into a plurality of data fields, and obtaining the number of interval wells corresponding to each section of data field; and based on geology and / or karst knowledge data of the work area to be evaluated, summarizing a relationship between the number distribution state of the primary produced fluid wells of the oil field area where each data field is located and fracture-cavity development distribution characteristics. The method can realize the characterization of the development and distribution characteristics of the large-range karst fractures and caves.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field development, and in particular to a method and system for characterizing the development and distribution characteristics of karst fractures and caves. Background Art

[0002] When describing the distribution characteristics of fracture-cavity carbonate rocks, various indirect data and methods should be used, including drilling coring data, seismic data, well logging data, well logging data, well kick, blowout, mud loss data during drilling, and development dynamic data accumulated during development.

[0003] In the existing technology, seismic and well logging are the main means, mainly starting from fault interpretation and karst zoning, to carry out three-dimensional structural characterization; then, seismic, well logging, core, imaging and other data are comprehensively used to characterize the distribution of karst reservoirs and dissolution pores of different origins. In addition, some scholars have investigated the typical karst outcrops in Yijianfang area, used modern measurement methods such as high-precision photography, drone aerial photography, and three-dimensional laser scanning, collected multi-source data and established an integrated digital outcrop model, combined with structural trace analysis and geochemical test results, and systematically studied the spatial distribution, filling structure and formation evolution characteristics of Yijianfang fracture-cavity bodies. In addition, some scholars have carried out quasi-interference well test analysis between adjacent wells in the fault zone based on production test data, studied the connectivity and reservoir energy of the fracture-cavity system, and thus obtained the development and distribution characteristics of fracture-pore-cavity reservoirs. Some scholars have analyzed the development characteristics of production wells based on the research on the distribution characteristics of reservoirs and the spatial relationship between oil and water in the study area, and proposed a dynamic analysis method for single well identification of multiple fracture-cavity bodies to identify different fracture-cavity bodies.

[0004] The above-mentioned existing technologies are all conventional methods for karst development characterization at present, and have good effects on small-scale karst development characterization. However, when carrying out large-scale karst development characterization, the workload of applying these methods increases exponentially and is often difficult to achieve.

[0005] However, the inventor of the present invention discovered during the process of implementing the present invention that the above-mentioned prior art did not propose a technical solution for characterizing the macroscopic distribution characteristics of karst by using the primary production fluid of a single well which has abundant data in the late stage of oil field development used on site. Summary of the invention

[0006] The purpose of the present invention is to provide a solution that can use the initial production fluid data of a single well to characterize the macroscopic distribution characteristics of karst.

[0007] In order to solve the above technical problems, an embodiment of the present invention provides a method for characterizing the development and distribution characteristics of karst fractures and caves, including: collecting the initial production fluid of each well in the work area to be evaluated; dividing the data range of the initial production fluid of the single well into multiple data domains according to the size range of the data value and obtaining the number of wells in the interval corresponding to each data domain; based on the geological and / or karstological knowledge of the work area to be evaluated, summarizing the relationship between the distribution state of the number of initial production wells in the oil field area where each data domain is located and the distribution characteristics of the fracture and cave development.

[0008] Preferably, the step of dividing the single-well initial fluid production data range into multiple data domains according to the data value size range and obtaining the number of interval wells corresponding to each data domain includes: dividing the single-well initial fluid production range of all wells into multiple segments according to the data value size range, and counting the number of interval wells corresponding to each data range; dividing the single-well initial fluid production data range into multiple data domains according to the number of interval wells in each data range.

[0009] Preferably, the step of dividing the single-well initial fluid production range of all wells into multiple segments according to the data value range includes: calculating the group interval for data statistics according to the maximum value of the single-well initial fluid production, wherein the group interval is calculated according to the following expression:

[0010] Z = λ(X, Y)

[0011] Y = {10 i}(i=0,1,2,3,......)

[0012] X=Lmax / 100

[0013] Among them, Z represents the group interval, the function of the λ function represents taking the minimum value greater than X from the sequence Y, and Lmax represents the maximum value of the initial production of the single well. According to the group interval, combined with the maximum and minimum values ​​of the initial production of the single well, the range of the initial production of the single well of all wells in the work area to be evaluated is divided into intervals.

[0014] Preferably, in the step of dividing the single well initial fluid production data range into multiple data domains according to the number of interval wells in each data range, it includes: judging whether two adjacent data ranges have a continuous interval relationship, wherein if the number of interval wells corresponding to the two adjacent data ranges are both non-zero values, then the current two adjacent data ranges have a continuous interval relationship; dividing several pairs of adjacent data ranges with a continuous interval relationship into primary intervals, and selecting the primary interval with the largest range as the target primary interval; taking the maximum and minimum values ​​of the current single well initial fluid production data range as boundaries, taking the remaining several intervals except the target primary interval as target secondary intervals; dividing the target primary interval into two target secondary intervals by binary search, so that all target secondary intervals are used as multiple data domains.

[0015] Preferably, the step of collecting the single-well initial production fluid of each well in the work area to be evaluated includes: associating the single-well initial production fluid data of each well with the well location coordinates.

[0016] Preferably, in the step of summarizing the relationship between the distribution state of the number of initial fluid production wells in the oil field area where each data domain is located and the distribution characteristics of fracture and cave development based on the geological and / or karstological knowledge data of the work area to be evaluated, the step includes: spreading the initial fluid production of each well in each data domain on a plane, and analyzing the distribution positions of the concentrated medium and high production areas in each data domain; and summarizing the relationship between the concentrated high production areas and the distribution characteristics of fracture and cave development in each data domain based on the geological and / or karstological knowledge data of the work area to be evaluated.

[0017] On the other hand, an embodiment of the present invention provides a computer-readable storage medium comprising a series of instructions for executing the method steps as described above.

[0018] In addition, an embodiment of the present invention further provides a system for characterizing the development and distribution characteristics of karst fractures and caves, comprising: a data collection module, which is configured to collect the initial production fluid of a single well of each well in the work area to be evaluated; a data statistics module, which is configured to divide the data range of the initial production fluid of a single well into multiple data domains according to the size range of the data value and obtain the number of wells in the interval corresponding to each data domain; a data summarization module, which is configured to summarize the relationship between the distribution state of the number of initial production fluid wells in the oil field area where each data domain is located and the development and distribution characteristics of fractures and caves based on the geological and / or karstological knowledge data of the work area to be evaluated.

[0019] Preferably, the data collection module is further configured to associate the single-well initial fluid production data of each well with the well location coordinates.

[0020] Preferably, the data summarization module includes: a distribution processing unit, which is configured to distribute the initial production fluid of each well in each data domain on a plane and analyze the distribution position of the concentrated medium and high-yield areas in each data domain; a development law generation unit, which is configured to summarize the relationship between the concentrated high-yield areas and the fracture and cave development distribution characteristics in each data domain based on the geological and / or karst knowledge data of the work area to be evaluated.

[0021] Compared with the prior art, one or more embodiments of the above scheme may have the following advantages or beneficial effects:

[0022] The present invention proposes a method and system for characterizing the development and distribution characteristics of karst fractures and caves. The method and system first construct a basic data table of well location coordinates and initial production fluid; then group and divide each well into different domains, and on this basis, make a plan distribution map of the well locations in different domains, combine the actual situation of the study area, and integrate other related research understandings to summarize the development and distribution characteristics of oilfield fractures and caves. In this way, the present invention can achieve the characterization of the development and distribution characteristics of karst fractures and caves in a large area (for example, within the entire Tahe Oilfield work area). The method is simple and easy to implement, and the characterization effect basically conforms to the geological understanding of the target work area, providing evidence for regional macroscopic geological research.

[0023] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 A schematic diagram of the steps of a method for characterizing the development and distribution characteristics of karst fractures and caves according to an embodiment of the present application.

[0026] Figure 2 The present invention is a schematic diagram of a specific implementation process of the method for characterizing the development and distribution characteristics of karst fractures and caves according to an embodiment of the present application.

[0027] Figure 3 This is an example distribution diagram of all wells with initial fluid production in the first example of the method for characterizing the development and distribution characteristics of karst fractures and caves according to an embodiment of the present application.

[0028] Figure 4 This is an example distribution diagram of wells with initial fluid production data greater than 400 (tons / day) in the first example of the method for characterizing the development and distribution characteristics of karst fractures and caves in an embodiment of the present application.

[0029] Figure 5 This is an example distribution diagram of wells with initial fluid production data in the range of 200 to 400 (tons / day) in the first example of the method for characterizing the development and distribution characteristics of karst fractures and caves in an embodiment of the present application.

[0030] Figure 6 This is an example distribution diagram of wells with initial fluid production data less than 200 (tons / day) in the first example of the method for characterizing the development and distribution characteristics of karst fractures and caves in an embodiment of the present application.

[0031] Figure 7This is a module block diagram of a system for characterizing the development and distribution characteristics of karst fractures and caves according to an embodiment of the present application. DETAILED DESCRIPTION

[0032] The following will describe the implementation methods of the present invention in detail with reference to the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0033] In addition, the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that here.

[0034] The terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments. Unless the context clearly indicates otherwise, the singular forms "one", "one" and "item" used herein are also intended to include plural numbers. It should also be understood that the terms "include" and / or "comprise" used herein specify the existence of stated features, integers, steps, operations, units and / or components, without excluding the existence or addition of one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0035] When describing the distribution characteristics of fracture-cavity carbonate rocks, various indirect data and methods should be used, including drilling coring data, seismic data, well logging data, well logging data, well kick, blowout, mud loss data during drilling, and development dynamic data accumulated during development.

[0036] In the existing technology, seismic and well logging are the main means, mainly starting from fault interpretation and karst zoning, to carry out three-dimensional structural characterization; then, seismic, well logging, core, imaging and other data are comprehensively used to characterize the distribution of karst reservoirs and dissolution pores of different origins. In addition, some scholars have investigated the typical karst outcrops in Yijianfang area, used modern measurement methods such as high-precision photography, drone aerial photography, and three-dimensional laser scanning, collected multi-source data and established an integrated digital outcrop model, combined with structural trace analysis and geochemical test results, and systematically studied the spatial distribution, filling structure and formation evolution characteristics of Yijianfang fracture-cavity bodies. In addition, some scholars have carried out quasi-interference well test analysis between adjacent wells in the fault zone based on production test data, studied the connectivity and reservoir energy of the fracture-cavity system, and thus obtained the development and distribution characteristics of fracture-pore-cavity reservoirs. Some scholars have analyzed the development characteristics of production wells based on the research on the distribution characteristics of reservoirs and the spatial relationship between oil and water in the study area, and proposed a dynamic analysis method for single well identification of multiple fracture-cavity bodies to identify different fracture-cavity bodies.

[0037] The above-mentioned existing technologies are all conventional methods for karst development characterization at present, and have good effects on small-scale karst development characterization. However, when carrying out large-scale karst development characterization, the workload of applying these methods increases exponentially and is often difficult to achieve.

[0038] However, the inventor of the present invention discovered during the process of implementing the present invention that the above-mentioned prior art did not propose a technical solution for characterizing the macroscopic distribution characteristics of karst by using the primary production fluid of a single well which has abundant data in the late stage of oil field development used on site.

[0039] In order to solve the technical problems in the above-mentioned background technology, the embodiment of the present application proposes a method and system for characterizing the development and distribution characteristics of karst fractures and caves. The method and system use the single well initial production fluid data with relatively rich data in the late stage of oil field development to achieve the characterization of the macroscopic development and distribution characteristics of karst fractures and caves in large oil field work areas. In this way, the problem of the huge workload of large-scale karst development characterization is overcome.

[0040] Figure 1 Schematic diagram of the steps of the method for characterizing the development and distribution characteristics of karst fractures and caves in the embodiment of the present application. Figure 1As shown, the method for characterizing the development and distribution characteristics of karst fractures and caves described in the embodiment of the present invention (hereinafter referred to as the "development characteristic characterization method") includes the following steps: First, step S110 collects the single well initial fluid production data of each well in the work area to be evaluated. Step S120, according to the size range of the data value, divides all the collected single well initial fluid production data ranges into multiple data domains, and obtains the number of interval wells corresponding to each data range. In step S120, it is necessary to count the number of wells belonging to the corresponding data range in each data range. Step S130 summarizes the relationship between the distribution state of the number of initial fluid production wells in the oil field area where each data domain is located and the development and distribution characteristics of fractures and caves based on the geological and / or karstological knowledge of the work area to be evaluated.

[0041] Figure 2 This is a schematic diagram of a specific implementation process of the method for characterizing the development and distribution characteristics of karst fractures and caves in the embodiment of the present application. Figure 1 and Figure 2 , the specific steps of the developmental feature characterization method described in the embodiment of the present invention are described.

[0042] In step S110, first, based on the dynamic data and static data of the oil and gas fields in the work area to be evaluated, the initial fluid production data of each well drilled in the work area to be evaluated is collected, and combined with the well location coordinate data of each well drilled in the work area to be evaluated, the initial fluid production data of each well is associated with the well location coordinates to construct a basic data table of initial fluid production and well location coordinates of the work area to be evaluated.

[0043] The above-mentioned development characteristic characterization method is applied to a target work area (for example, Tahe Oilfield) and the implementation process and application effect of the present invention are specifically described by taking the first example.

[0044] Due to the accumulation of long-term work in oil and gas field exploration and development, the data on the initial production of single wells is very rich, especially for large and super-large oil and gas fields. According to the well location data table of the target work area, the total number of wells drilled in the current work area is about 2,080, of which 1,706 wells have the data on the initial production of single wells (from the single well-draining, leakage-production test data table of the target work area).

[0045] In step S120, first, according to the data value range (maximum value and minimum value) of the single well initial production fluid, the single well initial production fluid range of all wells in the target work area is divided into multiple sections, and the number of wells corresponding to each data range (interval well number) is counted. Then, according to the interval well number of each data range, the single well initial production fluid data range is divided into multiple data domains.

[0046] Specifically, in the process of dividing the single well initial production range of all wells into multiple segments according to the size range of data values, such as Figure 2As shown, according to the basic data table of single well initial production fluid and well position coordinates obtained in step S110, according to the numerical range formed by the maximum and minimum values ​​of the single well initial production fluid, the group interval used for data statistics is calculated according to the maximum value of the single well initial production fluid.

[0047] The group distance is calculated according to the following expression:

[0048] Z = λ(X, Y) (1)

[0049] Y = {10 i}(i = 0, 1, 2, 3,... ...) (2)

[0050] X=Lmax / 100 (3)

[0051] Among them, Z represents the group interval, the function of the λ function represents taking the minimum value greater than X from the sequence Y, and Lmax represents the maximum value of the initial fluid production of a single well.

[0052] Taking the target work area in the first example as an example, the maximum value of the initial liquid production of a single well in Tahe Oilfield is 695.6 tons / day. From the above expression (3), it can be easily obtained that: X = 695.6 / 100 = 6.956, which is closest to 10 in the sequence Y, so the group interval value used for data statistics is determined to be 10 (tons / day). Based on this, the statistical results of the number of wells in the initial liquid production of a single well in Tahe Oilfield are obtained, and the total number of wells involved in the statistical analysis is 1706.

[0053] Then, according to the calculated group interval value, combined with the maximum and minimum values ​​of the single well initial production fluid, the range of the single well initial production fluid of all wells in the evaluation area is divided into intervals. Specifically, the minimum value of the single well initial production fluid is used as the starting value, and each interval group interval value is used to divide a data interval, and so on, so that the maximum value of the single well initial production fluid is used as the ending value. In this way, the embodiment of the present invention can count the data interval to which the single well initial production fluid data of each well belongs, thereby counting the number of wells corresponding to each data interval.

[0054] Taking the target work area in the first example as an example, after calculating the group interval value to be 10, each well in the work area can be grouped according to the group interval value and the size range of the initial liquid production of the single well. Among them, the number of wells in each group is counted according to the group interval of 10, and the statistical results are shown in Table 1:

[0055] Table 1 Statistical results of grouping target work areas based on group interval 10

[0056]

[0057]

[0058] Therefore, after counting the number of interval wells in each data range, step S120 will further divide the single well initial production data range into multiple data domains according to the number of interval wells in each data range, so as to obtain the number of interval wells corresponding to each data domain.

[0059] Specifically, the first step is to determine whether there is a continuous interval relationship between two adjacent data ranges. Among them, if the number of interval wells corresponding to the two adjacent data ranges are all non-zero values, then the current two adjacent data ranges have a continuous interval relationship. If the number of interval wells corresponding to the two adjacent data ranges is zero, then the current two adjacent data ranges do not have a continuous interval relationship. The second step is to divide several pairs of adjacent data ranges with a continuous interval relationship into primary intervals, and select the primary interval with the largest range as the target primary interval. The third step is to use the maximum and minimum values ​​of the current single well initial production fluid data range as boundaries, and use the remaining several intervals except the target primary interval as target secondary intervals. The fourth step is to divide the target primary interval into two target secondary intervals through dichotomy, so that all target secondary intervals are used as multiple data domains.

[0060] Taking the target work area in the first example as an example, on the basis of the single well initial production liquid classification realized based on Table 1, the "domain" is divided according to the data distribution characteristics: As can be seen from Table 1, the distribution characteristics of the wells with the initial production of single wells in Tahe Oilfield are: in the range of 0.3-390 (tons / day), 400-420 (tons / day), 440-460 (tons / day), 470-500 (tons / day), etc., there are multiple first-level intervals with continuous relationships; 0.3-390 (tons / day) is selected as the target first-level interval; with the maximum value (695.6 tons / day) and the minimum value (0.3 tons / day) of the current single well initial production liquid data range as the boundary, the distribution of wells in the range of 0.3-390 (tons / day) in each statistical interval is continuous, and it is used as the target first-level interval, and the distribution of wells in the range of 390-695.6 (tons / day) in each statistical interval is discontinuous, and it is used as the target second-level interval.

[0061] According to this feature, and to facilitate subsequent comparative analysis, the large domain is defined as two, 0-400 (tons / day) large domain and greater than 400 (tons / day) large domain. Based on this, and according to actual needs, the "binary method" is used to further divide the target first-level interval into "domains". The final data domain division results are shown in Table 2.

[0062] Table 2 Data domain division results

[0063]

[0064] In this way, after the collected single-well data value range is divided into multiple data domains, step S120 can obtain the number of interval wells corresponding to each data domain, thereby entering step S130.

[0065] In step S130, first, the initial production of each well in each data domain is spread on a plane, and the distribution positions of the concentrated medium and high-yield areas in each data domain are analyzed; then, based on the geological and / or karst knowledge data of the work area to be evaluated, the relationship between the concentrated high-yield areas in each data domain and the fracture and cave development and distribution characteristics is summarized, so as to deepen the understanding of the development and distribution laws of carbonate fractures and caves in the target work area.

[0066] Taking the target work area in the first example above as an example, the distribution of all wells in the target work area on the plane is expressed in different domains:

[0067] Make a plane distribution map of well locations in different regions, such as Figure 3 , Figure 4 , Figure 5 and Figure 6 For the convenience of analysis and comparison, Figure 3 to Figure 6 In the figure, two stratigraphic (erosion) pinch-out lines are added. The dotted curve marked with a circle represents the (erosion) pinch-out line of the Sangtamu Formation of the Upper Ordovician in the Tahe Oilfield, and the dotted curve marked with a triangle represents the (erosion) pinch-out line of the Tongjianfang Formation of the Upper Ordovician. Among them, the (erosion) pinch-out line of the Sangtamu Formation can be divided into SW, NW and nearly EW directions from east to west according to its trend. The turning points of its trend are marked as "p1" and "p2" to indicate the three-segment division results of the Sangtamu Formation (erosion) pinch-out line. In addition, in order to better study the distribution area of ​​high-yield wells, Figure 3 to Figure 6 Three orange auxiliary lines (k1, k2, k3) running nearly north-south and four blue auxiliary lines (L1, L2, L3, L4) running northeast-southwest are also added.

[0068] Figure 3 The plan distribution diagram of all wells with initial production data is shown. It can be seen that the well distribution is relatively uniform, which lays a good foundation for the subsequent statistical analysis. It should be noted that the so-called concentrated development area is exclusive. If the area is concentrated with high-yield wells and medium-yield wells, only the high-yield wells will be recognized, and so on.

[0069] Figure 4The plan distribution of 17 wells in the Ordovician carbonate reservoir of Tahe Oilfield with a single well initial liquid production (volume) greater than 400 (tons / day). In the large area greater than 400, the maximum single well initial liquid production is 695.6 tons / day, which is very high. The number of wells is very small, accounting for less than 1% of the total number of wells. Among these 17 wells, 12 wells are distributed in the concave part on the north side of the pinch-out line of the Sangtamu and Yijianfang formations, 3 wells are distributed in the concave part between the pinch-out line of the Yijianfang formation and the Sangtamu formation, and 2 wells are distributed south of the pinch-out line of the Sangtamu formation. The distribution is very concentrated.

[0070] Figure 5 The plan distribution of 101 wells with a single well initial liquid production of 400-200 (tons / day) is shown. The number of wells is not large, accounting for 5.9% of the total number of wells. Some of them are relatively concentrated in the concave part on the north side of the pinch-out line of the Sangtamu and Yijianfang formations, which is highly overlapped with the concentrated area of ​​wells with initial liquid production greater than 400 (tons / day). Another part is scattered in the southwest of the Sangtamu pinch-out line. In addition, there are several isolated points distributed in other areas.

[0071] Figure 6 The plan distribution of wells with initial liquid production of less than 200 (tons / day) is shown. Its characteristics are: First, there are many wells, up to 1,589 wells, accounting for 93.3% of the total number of wells, which are widely distributed in the whole area, and the main concentrated development area is the northwest of the Yijianfang pinch-out line.

[0072] Next, combined with the actual situation of the study area and comprehensive other relevant data, the relationship between it and the development and distribution characteristics of fractures and caves is summarized to deepen the understanding of the development and distribution laws of carbonate fractures and caves.

[0073] According to the development experience in the Tahe area, under the condition of roughly the same formation energy, for fracture-cavity carbonate rocks, the stronger the dissolution, the more developed the caves and fractures, the larger the scale, and the higher the initial fluid production of a single well. Therefore, the fractures and caves are most developed in the area where wells with an initial fluid production of more than 400 (tons / day) are relatively concentrated. This area is in the Figure 4 As shown in the figure, the pinch-out line of the Yijianfang Formation and the Sangtamu Formation is concave to the south. From a geological point of view, this area is located at a high position and is in an erosion zone. It is strongly affected by weathering and dissolution, and fractures and caves are concentrated. Moreover, due to its high position, oil and gas accumulation is favorable. Therefore, the predicted area basically conforms to the laws of geological cognition. The relatively concentrated area of ​​wells with an initial fluid production of 400-200 (tons / day) has a moderate degree of fracture and cave development, such as Figure 5 Southwest of the Sangtamu pinch-out line. From a geological perspective, this area is a covered area, located at an absolute low position, with strong dissolution, controlled by faults, and a moderate degree of fracture and cave development, which is consistent with the above-mentioned single well initial production prediction. The fracture and cave development degree in the concentrated area of ​​wells with less than or equal to 200 (tons / day) is low, such as Figure 6From a geological point of view, the northwest of the Santamu tip line is located at a relatively high position and is an erosion zone, which is greatly affected by weathering. However, due to its relatively high position, the dissolution effect is limited, resulting in a low degree of development of fractures and caves in this area, which is also consistent with the predicted area of ​​initial fluid production of a single well.

[0074] In addition, based on the above method for characterizing the development and distribution characteristics of karst fractures and caves, an embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored, and the computer program is executed to run a method for characterizing the development and distribution characteristics of karst fractures and caves. The computer program can run computer instructions, and the computer instructions include computer program code, which can be in source code form, object code form, executable file or some intermediate form, etc.

[0075] Computer-readable storage media may include: any entity or device that can carry computer program code, recording media, USB flash drives, mobile hard disks, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0076] It should be noted that the content contained in computer-readable storage media can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, the content contained in computer-readable storage media does not include electrical carrier signals and telecommunication signals.

[0077] On the other hand, based on the above-mentioned method for characterizing the development and distribution characteristics of karst fractures and caves, an embodiment of the present invention also provides a system for characterizing the development and distribution characteristics of karst fractures and caves (also referred to as a "development characteristic characterization system").

[0078] Figure 7 Module block diagram of the system for characterizing the development and distribution characteristics of karst fractures and caves according to an embodiment of the present application. Figure 7 As shown, the production situation evaluation system described in the embodiment of the present invention includes: a data collection module 71, a data statistics module 72 and a data induction module 73.

[0079] Specifically, the data collection module 71 is implemented according to the method described in step S110, and is configured to collect the initial production fluid of each well in the work area to be evaluated; the data statistics module 72 is implemented according to the method described in step S120, and is configured to divide the data range of the initial production fluid of a single well into multiple data domains according to the size range of the data value and obtain the number of wells in the interval corresponding to each data domain; the data induction module 73 is implemented according to the method described in step S130, and is configured to summarize the relationship between the distribution status of the number of initial production fluid wells in the oil field area where each data domain is located and the distribution characteristics of the fracture and cave development based on the geological and / or karst knowledge data of the work area to be evaluated.

[0080] Furthermore, in one embodiment, the data collection module 71 is also configured to associate the single-well initial fluid production data of each well with the well location coordinates.

[0081] Further, in one embodiment, the data summarization module 73 includes: a distribution processing unit 731 and a development law generation unit 732. Specifically, the distribution processing unit 731 is configured to distribute the single well initial production fluid of each well in each data domain on a plane, and analyze the distribution position of the concentrated medium and high production areas in each data domain; the development law generation unit 732 is configured to summarize the relationship between the concentrated high production areas and the fracture and cave development distribution characteristics in each data domain based on the geological and / or karst knowledge data of the work area to be evaluated.

[0082] The present invention discloses a method and system for characterizing the development and distribution characteristics of karst fractures and caves. The method and system first construct a basic data table of well location coordinates and initial production fluid; then group and divide each well into different domains, and on this basis, make a plan distribution map of well locations in different domains, combine the actual situation of the study area, and integrate other related research understandings to summarize the development and distribution characteristics of oilfield fractures and caves. In this way, the present invention can achieve the characterization of the development and distribution characteristics of karst fractures and caves in a large area (for example, within the entire Tahe Oilfield work area), the method is simple and easy to implement, and the characterization effect basically conforms to the geological understanding of the target work area, providing evidence for regional macroscopic geological research.

[0083] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any person familiar with the technology within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0084] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0085] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0086] It should be understood that the embodiments disclosed in the present invention are not limited to the specific structures, processing steps or materials disclosed herein, but should be extended to equivalent substitutions of these features understood by ordinary technicians in the relevant field. It should also be understood that the terms used herein are only used for the purpose of describing specific embodiments and are not meant to be limiting.

[0087] The "one embodiment" or "embodiment" mentioned in the specification means that the specific features, structures or characteristics described in conjunction with the embodiment are included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment" or "embodiment" appearing in various places throughout the specification do not necessarily refer to the same embodiment.

[0088] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for characterizing the development and distribution characteristics of karst fractures and caves, characterized in that: include: Collect the initial production fluid of each well in the work area to be evaluated; According to the range of data values, the single well initial production data range is divided into multiple data domains and the number of interval wells corresponding to each data domain is obtained; Based on the geological and / or karstological data of the work area to be evaluated, the relationship between the distribution status of the number of wells with initial liquid production and the distribution characteristics of fracture-cavity development in the oilfield area where each data domain is located is summarized.

2. The method according to claim 1, characterized in that: The step of dividing the single well initial production data range into multiple data domains according to the data value range and obtaining the number of interval wells corresponding to each data domain includes: According to the range of data values, the single-well initial production range of all wells is divided into multiple sections, and the number of interval wells corresponding to each data range is counted; According to the number of interval wells in each data range, the single well initial fluid production data range is divided into multiple data domains.

3. The method according to claim 2, characterized in that The step of dividing the single well initial fluid production range of all wells into multiple segments according to the size range of data values ​​includes: According to the maximum value of the initial fluid production of a single well, the group interval used for data statistics is calculated, wherein the group interval is calculated according to the following expression: Z = λ(X, Y) Y={10 i }(i=0,1,2,3,......) X=Lmax / 100 Wherein, Z represents the group interval, the function of the λ function represents taking the minimum value greater than X from the sequence Y, and Lmax represents the maximum value of the initial fluid production of a single well; According to the group interval, combined with the maximum and minimum values ​​of the initial fluid production of the single well, the range of the initial fluid production of the single well of all the wells in the work area to be evaluated is divided into intervals.

4. The method according to claim 2 or 3, characterized in that: The step of dividing the single well initial production fluid data range into multiple data domains according to the number of interval wells in each data range includes: Determine whether two adjacent data ranges have a continuous interval relationship, wherein if the interval well numbers corresponding to the two adjacent data ranges are both non-zero values, then the two adjacent data ranges currently have a continuous interval relationship; Divide several pairs of adjacent data ranges with continuous interval relationship into first-level intervals, and select the first-level interval with the largest range as the target first-level interval; Taking the maximum and minimum values ​​of the current single well initial fluid production data range as boundaries, several intervals other than the target primary interval are taken as target secondary intervals; The target primary interval is divided into two target secondary intervals by a dichotomy method, so that all target secondary intervals are used as multiple data domains.

5. The method according to any one of claims 1 to 4, characterized in that: The steps of collecting the initial production fluid of each well in the work area to be evaluated include: The single well initial fluid production data of each well were associated with the well location coordinates.

6. The method according to any one of claims 1 to 5, characterized in that: The step of summarizing the relationship between the distribution state of the number of wells with initial liquid production and the distribution characteristics of fracture-cavity development in the oil field area where each data domain is located based on the geological and / or karstological knowledge data of the work area to be evaluated includes: The single well initial production of each well in each data domain is spread on a plane, and the distribution position of the concentrated medium and high production areas in each data domain is analyzed; Based on the geological and / or karstological knowledge of the work area to be evaluated, the relationship between the concentrated high-yield areas and the distribution characteristics of fracture and cave development in each data domain is summarized.

7. A computer-readable storage medium, characterized in that: It contains a series of instructions for executing the method steps as claimed in any one of claims 1 to 6.

8. A system for characterizing the development and distribution characteristics of karst fractures and caves, characterized in that: include: A data collection module configured to collect the initial production fluid of each well in the work area to be evaluated; A data statistics module is configured to divide the single well initial production data range into multiple data domains according to the data value range and obtain the number of interval wells corresponding to each data domain; The data summarization module is configured to summarize the relationship between the distribution state of the number of initial liquid production wells and the distribution characteristics of fracture-cavity development in the oil field area where each data domain is located based on the geological and / or karst knowledge data of the work area to be evaluated.

9. The system according to claim 8, characterized in that The data collection module is further configured to associate the single-well initial fluid production data of each well with the well location coordinates.

10. The system according to claim 8 or 9, characterized in that The data summarization module comprises: A distribution processing unit configured to distribute the single well initial production fluid of each well in each data domain on a plane, and analyze the distribution position of the concentrated medium and high production areas in each data domain; The development law generating unit is configured to summarize the relationship between the concentrated high-yield areas and the fracture-cavity development distribution characteristics in each data domain based on the geological and / or karst knowledge data of the work area to be evaluated.

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