A method and chart for producing dynamic data combined with test data to identify fractures

Abstract

The present application belongs to the technical field of oil and gas field development, and provides a method and chart for identifying fractures by combining production dynamic data with test data; the method collects oil field basic and production dynamic data; according to tracer test data and water breakthrough analysis data, the reservoir type is preliminarily divided; further, a fracture identification chart is established; the production dynamic data of well groups without tracer test data and water breakthrough analysis data are introduced into the fracture identification chart, and the fractures among well groups are identified according to the data falling into the reservoir classification interval. The method only needs to combine the existing tracer test data and water breakthrough analysis data with the oil field daily production dynamic data to complete the identification of fractures among well groups, and solves the problems of high difficulty in fracture identification, high requirement for data quality and precision, high test cost, long cycle time and the like in the prior art.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil and gas field development, and provides a method for identifying fractures by combining production dynamic data with test data and a chart. BACKGROUND

[0002] Fractures are an important oil and gas reservoir space and a good channel for underground fluid seepage. The existence and development degree of fractures have a dual effect on the water injection development of an oil reservoir. On the one hand, the existence of fractures in an oil reservoir reservoir is equivalent to a high-permeability channel, which improves the recovery rate of an oil well. On the other hand, the existence of fractures also enhances the heterogeneity of the reservoir, which may cause directional water channeling between oil and water wells to some extent. Therefore, identifying fractures in an oil reservoir can provide important guidance for efficient exploitation of an oilfield.

[0003] Existing fracture identification technologies include core observation, tracer test, water breakthrough and effect analysis, well logging technology, and water drive front test, etc. These identification technologies mainly verify the existence of fractures by testing the oil reservoir core, fluid and tracer.

[0004] In "Research on the identification method of fracture network in fractured carbonate rock reservoirs—take the application of F buried hill reservoir in Shengli oilfield as an example", Zhang Liyan pointed out that core observation is the most direct means to identify fractures, which can directly judge the type and shape of fractures. However, in the fracture development section, the core acquisition rate is very low, and only medium and small fractures are observed, and the core acquisition cost is also very high.

[0005] In "Application of production dynamic data in fracture identification in Bai 209 area of Baibao oilfield", Wang Xiqiang mentioned that interwell tracer monitoring technology can identify large channels and judge fault sealing, which has important value for understanding fractures. However, due to the limitation of the number and cost of tracer tests, it is impossible to characterize the fractures of the whole oil reservoir.

[0006] Chinese invention patent application CN109425912A discloses a method for identifying effective fractures in carbonate rock reservoirs, which identifies the effective fractures of the reservoir by analyzing the difference between the resistivity of the base rock of the reservoir section and the deep lateral resistivity, and can accurately and reliably identify the fracture development section of the reservoir, providing a basis for the reasonable and effective development of carbonate rock fractured reservoirs. However, there are still problems such as low accuracy due to limited well logging data.

[0007] Chinese invention patent application CN114202437A discloses a method for obtaining production spectrum of a target well at different production stages by time domain transformation of production dynamic data of the target well at different production stages to frequency domain, and finally obtaining the volume of each fracture-cave type of the target well at each production stage through quantitative analysis of the production spectrum; this method also needs to transform the production dynamic data from time domain to frequency domain by means of a transformation module of the device, and to process the subsequent production dynamic data by means of a data analysis and volume calculation module.

[0008] In actual mine development, the fracture identification technology is often limited in accuracy due to small number of sample tests and low data quality, high cost and long period of single test, which brings certain difficulties to fracture identification. Therefore, the present application proposes a method for identifying fractures by combining production dynamic data of oil and water wells with test data. SUMMARY

[0009] To solve the problems of high cost and long period in identifying fractures by tracer test and water breakthrough analysis in the prior art, and the problem of poor identification accuracy caused by small amount of production dynamic data in logging technology, the present application provides a method and chart for identifying fractures by combining production dynamic data with test data, establishes a fracture identification chart according to the production dynamic data of existing tracer test data and water breakthrough analysis data, and imports the production dynamic data without tracer test data and water breakthrough analysis data into the chart to identify the corresponding fractures; the chart of the present application includes fracture identification relationship charts for reservoirs under different conditions, and appropriate relationship charts can be selected for fracture identification according to actual reservoir conditions and existing data conditions.

[0010] One of the objects of the present application is to provide a method for identifying fractures by combining production dynamic data with test data, which specifically includes the following steps:

[0011] Step 1: Collecting oilfield basic and production dynamic data:

[0012] Collecting basic and production dynamic data of injection-production well groups in the study area, including basic geologic parameters of the reservoir, production data of oil and water wells, well location data, tracer test data and water breakthrough analysis data;

[0013] Step 2: Analyzing reservoir types:

[0014] Preliminarily classifying reservoir types according to the tracer test data and water breakthrough analysis data;

[0015] Step 3: Establishing a fracture identification chart:

[0016] According to the preliminarily classified reservoir types, dividing the reservoir classification intervals, and establishing a fracture identification chart;

[0017] Step 4: Identifying fractures:

[0018] Production dynamic data of injection-production well groups in the study area are imported into the fracture identification chart, and fractures between well groups are identified based on the reservoir type range into which the data falls.

[0019] Furthermore, the basic geological parameters of the reservoir are one or more of the following: formation coefficient, permeability, and reservoir thickness.

[0020] The oil and water well production data includes one or more of the following: monthly water cut increase rate, oil and water well production date, monthly average daily fluid production, monthly average daily oil production, daily oil production decline rate, bottom hole flowing pressure, and oil production per meter of flowing pressure unit pressure drop.

[0021] The well location data includes one or both of the well location coordinates and the injection-production well distance.

[0022] The tracer test data is the water drive velocity.

[0023] The water breakthrough analysis data includes the water thrust rate and the injection-production well spacing.

[0024] Furthermore, in step two, the reservoir type includes three types: porous, fracture-porous, and fractured.

[0025] Furthermore, in step three, the crack identification diagram includes at least one of eight relationship diagrams; specifically, the relationship diagrams are:

[0026] ①: Relationship between average formation coefficient / injection-production well spacing ratio and hydraulic thrust rate;

[0027] ②: A graph showing the relationship between the monthly rate of increase in water cut when the water cut of an oil well reaches a stable level of 50%, calculated based on the injection time of the corresponding water injection well, and the monthly rate of increase in water cut when the water cut of an oil well reaches a stable level of 50% or higher, calculated based on the water breakthrough time of the oil well.

[0028] ③: Relationship between the average formation coefficient / injection-production well distance ratio and the monthly water cut increase rate when the water cut of the oil well reaches a stable level of 50% or more, calculated based on the water breakthrough time of the oil well;

[0029] ④: Relationship between injection-production well spacing and the monthly rate of increase in water cut when the water cut of the oil well is stably above 75%;

[0030] ⑤: Relationship between the average formation coefficient / injection-production well spacing ratio and the monthly water cut increase rate when the water cut of water-bearing oil wells stably reaches 75% or more;

[0031] ⑥: A graph showing the relationship between the absolute decrease in the average daily oil production of oil wells and the rate of decline in the average daily oil production of oil wells;

[0032] ⑦: Relationship between the absolute decrease in monthly average daily fluid production and the absolute decrease in monthly average daily oil production;

[0033] 8: The relationship between the absolute decline of the bottom hole flowing pressure and the oil production per meter per unit pressure drop of the flowing pressure.

[0034] Further, in step four, the production performance data of the injection-production well group in the study area can be one or more of the basic geological parameters of the reservoir, the production data of the oil and water wells, and the well location data.

[0035] In some embodiments of the present application, for the reservoirs between conventional oil wells, the reservoir fracture identification is performed using the relationship graph 1.

[0036] Further, the purpose of using the average formation coefficient to injection-production well spacing ratio in the relationship graph 1 is to eliminate the influence of the injection-production well spacing.

[0037] In some embodiments of the present application, for the reservoirs with existing tracer test data and water breakthrough analysis data, the reservoir fracture identification is directly performed using the tracer test data and the water breakthrough analysis data.

[0038] In some embodiments of the present application, for the reservoirs in the medium water cut stage with the water cut of the water breakthrough well being more than 50%, the reservoir fracture identification is performed using the relationship graphs 2 or 3.

[0039] Further, the relationship graphs 2 or 3 are used to determine the reservoir type of the injection-production well group according to the water cut rising speed; the time of the water breakthrough of the oil well can be accurately determined by taking water samples on site, and the time when the water cut of the oil well is more than 50% after the water breakthrough can also be accurately determined, so that the month average water cut rising speed of the oil well when the water cut is more than 50% can be accurately calculated and used to replace the water cut rising rate to represent the influence of different reservoir types on the water cut rising speed.

[0040] Further, since there is a phenomenon of multiple injection water being affected by the injection water of multiple injection wells in the medium water cut stage, it is too one-sided to establish the relationship between the single oil-water well injection-production well spacing and the water cut rising speed, and it cannot accurately describe the relationship, so the relationship between the month water cut rising speed of the oil well when the water cut is more than 50% calculated according to the injection time of the corresponding injection well and the month water cut rising speed of the oil well when the water cut is more than 50% calculated according to the water breakthrough time of the oil well or the relationship between the average formation coefficient / injection-production well spacing ratio and the month water cut rising speed of the oil well when the water cut is more than 50% calculated according to the water breakthrough time of the oil well is used for fracture identification.

[0041] In some embodiments of the present application, for the reservoirs in the medium-high water cut stage with the water cut of the water breakthrough well being more than 75%, the reservoir fracture identification is performed using the relationship graphs 4 or 5.

[0042] Further, the month average water cut rising speed of the oil well calculated by the water cut is used to replace the water cut rising rate to represent the influence of different reservoir types on the water cut rising speed; in addition, for the reservoir in the middle and high water cut stage, the water cut rises rapidly, and the oil well and the injection well have an advantage channel, so the injection-production well spacing relationship between the oil well and the injection well can be used in this stage.

[0043] In some embodiments of the present application, for the dual medium reservoir in which the fracture conductivity decline will cause the reservoir liquid production capacity to decline, the relationship diagram (6) is used for reservoir fracture identification.

[0044] Further, since the fracture conductivity decline will cause the reservoir oil production capacity to decline, generally in the recoverable process, with the reservoir pressure decline in the fracture development section, the fracture may gradually close or the fracture opening decreases, resulting in the rapid decline of the fracture conductivity. Therefore, the threshold interval of the absolute decline amplitude of the month average daily oil production of the oil well in the statistical period and the month average daily oil production decline rate of the oil well in the statistical period are used to identify the fracture development section.

[0045] In some embodiments of the present application, for the dual medium reservoir in which the fracture conductivity decline will cause the reservoir liquid production capacity to decline, the relationship diagram (7) is used for reservoir fracture identification.

[0046] Further, since the fracture conductivity decline will cause the reservoir liquid production capacity to decline, generally in the recoverable process, with the reservoir pressure decline, the fracture may gradually close or the fracture opening decreases, resulting in the rapid decline of the conductivity, that is, the decline of the liquid production and oil production capacity, even if the energy is supplemented by water injection in the later period, the liquid production capacity of the fracture development section is difficult to recover or maintain the stable liquid discharge capacity, and generally the fracture-pore type reservoir with fracture type or mainly fracture conductivity is difficult to sustain stable production for more than two years. Therefore, for the tracer test well group, after the reservoir type of the oil-water well connection between the oil well and the water well is determined, the absolute decline amplitude of the month average daily oil production of the oil well in the statistical period and the absolute decline amplitude of the month average daily liquid production are calculated.

[0047] In some embodiments of the present application, for the reservoir with stable work system and stable formation pressure, the relationship diagram (7) is used for reservoir fracture identification.

[0048] Further, under the condition of stable oil well operation system and relatively stable formation pressure, the decline range of bottom hole flowing pressure can reflect the oil production capacity of different reservoir sections of unit pressure drop under different reservoir types. In the complex condition of unstable formation pressure, the decline range of bottom hole flowing pressure cannot represent the amplification degree of production pressure difference or the decline range of formation pressure; but in the dual medium reservoir with effective conductive fractures, the difference in conductive capacity of fractures and matrix will cause the difference in pressure drop range of fractures and matrix, and the pressure in the fractures changes relatively fast and has greater influence on bottom hole flowing pressure. Therefore, the relationship between oil production per meter under unit pressure drop and absolute decline range of bottom hole flowing pressure is used for fracture identification.

[0049] Further, the fracture identification chart further comprises: (8) a water drive velocity versus injection-production well spacing relationship chart and / or (9) a water push velocity versus injection-production well spacing relationship chart.

[0050] Further, the fracture identification method further comprises: verifying the result of fracture identification by using the water drive velocity versus injection-production well spacing relationship chart and the water push velocity versus injection-production well spacing relationship chart.

[0051] The second object of the present application is to provide a fracture identification chart for the fracture identification method of the production dynamic data combined with test data.

[0052] The third object of the present application is to provide the application of the fracture identification chart in reservoir fracture identification.

[0053] Further, the reservoirs include conventional reservoirs, medium water cut stage reservoirs with water cut of more than 50% in water breakthrough wells, medium-high water cut stage reservoirs with water cut of more than 75% in water breakthrough wells, dual medium reservoirs and reservoirs with stable operation system and stable formation pressure.

[0054] Compared with the prior art, the present application has the following beneficial effects:

[0055] 1. The present application establishes a fracture identification chart by the relationship between fracture response characteristics and reservoir types, and can be used for identifying the fractures in most conventional reservoirs, medium water cut stage reservoirs, medium-high water cut stage reservoirs and special reservoirs such as dual medium reservoirs.

[0056] 2. The method can identify fractures by using conventional production dynamic data of oil reservoirs combined with production test data, greatly saves the cost of tracer test, and has low requirement on the amount of production data.

[0057] 3. The overall coincidence rate of fracture identification by using the chart and the method is more than 90%, which is improved by more than 20% compared with the identification result of logging technology.

[0058] 4. The chart and method are suitable for realizing the fast and low-cost identification of the fractures between the groups of oilfield production wells, and provide strong support for the design and adjustment of the oilfield development plan. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1a Figure 1 is a graph of the relationship between the water drive speed and the reservoir type in the existing tracer test data of Example 1;

[0060] Figure 1b Figure 2 is a graph of the relationship between the water drive speed and the injection-production well spacing and the reservoir type in the existing water breakthrough analysis data of Example 1;

[0061] Figure 2 Figure 3 is a graph of the relationship between the average formation coefficient / injection-production well spacing ratio and the water drive speed of Example 1;

[0062] Figure 3 Figure 4 is a graph of the relationship between the month water cut rise speed at which the oil well water cut stably reaches 50% and the month water cut rise speed at which the oil well water cut stably reaches more than 50% calculated by the oil well water breakthrough time of Example 1;

[0063] Figure 4 Figure 5 is a graph of the relationship between the average formation coefficient / injection-production well spacing ratio and the month water cut rise speed at which the oil well water cut stably reaches more than 50% calculated by the oil well water breakthrough time of Example 1;

[0064] Figure 5a Figure 6 is a graph of the relationship between the injection-production well spacing and the month water cut rise speed at which the oil well water cut stably reaches more than 75% calculated by the injection time corresponding to the injection well of Example 1;

[0065] Figure 5b Figure 7 is a graph of the relationship between the injection-production well spacing and the month water cut rise speed at which the oil well water cut stably reaches more than 75% calculated by the oil well water breakthrough time of Example 1;

[0066] Figure 6 Figure 8 is a graph of the relationship between the average formation coefficient / injection-production well spacing ratio and the month water cut rise speed at which the water breakthrough oil well water cut stably reaches more than 75% of Example 1;

[0067] Figure 7 Figure 9 is a graph of the relationship between the absolute decline amplitude of the monthly average daily oil production of the oil well and the monthly average daily oil production decline rate of Example 1;

[0068] Figure 8 Figure 10 is a graph of the relationship between the absolute decline amplitude of the monthly average daily fluid production of the oil well and the absolute decline amplitude of the monthly average daily oil production of Example 1;

[0069] Figure 9 Figure 11 is a graph of the relationship between the absolute decline amplitude of the bottom hole flowing pressure and the oil production per meter per unit pressure drop of the flowing pressure of Example 1;

[0070] Figure 10 Figure for average formation coefficient / injection-production well spacing ratio versus water push rate for Example 2;

[0071] Figure 11 Figure for injection-production well spacing versus monthly water cut rise rate to reach 50% water cut for Example 3;

[0072] Figure 12 Figure for injection-production well spacing versus monthly water cut rise rate to reach 75% water cut for Example 4;

[0073] Figure 13 Figure for injection-production well spacing versus monthly water cut rise rate to reach 75% water cut for Example 4. DETAILED DESCRIPTION

[0074] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, each feature in each embodiment can be combined with each other, and all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0075] Example 1: Establishing a fracture identification chart

[0076] (1) Select a certain reservoir, collect the existing tracer test data, water breakthrough analysis data and other production performance data of the reservoir, such as reservoir basic geological parameters, oil and water well production data, well location data, etc. The specific data is shown in Table 1.

[0077] Table 1: Tracer test data, water breakthrough analysis data and other production performance data of the reservoir

[0078]

[0079]

[0080] Note: Column A - injection well number; Column B - production well number; Column C: injection-production well spacing (m); Column D: tracer test water push rate (m / d); Column E: water breakthrough analysis water push rate (m / d); Column F: average formation coefficient of drive section (md.m); Column G: KH / L (md.m / m); Column H - monthly water cut increase rate to reach 75% stable water cut calculated from injection well injection time (% / month); Column I - monthly water cut increase rate to reach 75% stable water cut calculated from oil well water breakthrough time (% / month); Column J - monthly water cut increase rate to reach 75% stable water cut calculated from injection well injection time (% / month); Column K - monthly water cut increase rate to reach 75% stable water cut calculated from oil well water breakthrough time (% / month); Column L - absolute decrease amplitude of monthly average daily oil production during the statistical period (%); Column M - decline rate of monthly average daily oil production during the statistical period (%); Column N - absolute decrease amplitude of monthly average daily liquid production during the statistical period (%); Column O - absolute decrease amplitude of flowing pressure (%); Column P - oil production per MPa.m of unit pressure drop (t / MPa.m).

[0081] (2) The relationship between water drive velocity and water push velocity of existing tracer test data and water breakthrough analysis data and injection-production well spacing is used to divide the reservoir type connected between oil and water wells into three types of pore type, fracture-pore type and fracture type. The relationship diagram between water drive velocity and reservoir type in existing tracer test data is shown in Figure 1a , and the relationship diagram between water push velocity and injection-production well spacing and reservoir type in existing water breakthrough analysis data is shown in Figure 1b ; the reservoir type is divided into the reservoir classification intervals shown in Tables 2 and 3 according to the interval into which the data falls;

[0082] Table 2 Reservoir classification intervals

[0083] Indicator parameter Unit Pore type Fracture-pore type Fracture type Tracer test water flood rate (m / d) ＜90.3 90.3-247.2 ＞247.2

[0084] Table 3 Reservoir classification intervals

[0085]

[0086] (3) The formation coefficient per meter of horizontal connection in the above well group, i.e. the ratio of water push velocity, average formation coefficient and injection-production well spacing of each well group, is calculated, and the relationship diagram between it and water push velocity in water breakthrough analysis data is established, as shown in Figure 2 ; the reservoir type is divided into the reservoir classification intervals shown in Table 4 according to the interval into which the data falls;

[0087] Table 4 Reservoir classification intervals

[0088] Indicator parameter Unit Pore type Fracture-pore type Fracture type See water analysis data water push rate (m / d) ＜2.4 ≥2.4 ≥2.4 Average formation factor / drive distance (md.m / m) ＜0.75 ≤1.86 ＜1.86

[0089] (4) For oil wells in the medium water cut stage (water cut stably reaches 50% or more):

[0090] Select the monthly water cut increase rate and oil / water well production date data from the oil and water well production data;

[0091] The monthly rate of increase in water cut when the water cut of an oil well stably reaches 50% or more is calculated based on the injection time of the corresponding water injection well: 50% / (date when the water cut of the oil well stably reaches 50% - date when the water cut of the corresponding water injection well is injected);

[0092] A water cut of 50% means that the water cut of the oil well has been stable at 50% or more for three consecutive months, with the date in months.

[0093] The monthly rate of increase in water cut, calculated based on the time it takes for the well to reach water, is: 50% / (date when the water cut of the well reaches 50% - date when the well is put into production).

[0094] A water cut of 50% means that the water cut of an oil well has remained stable at 50% or higher for three consecutive months, with the date in months.

[0095] Establish a graph showing the relationship between the monthly water cut increase rate when the water cut of an oil well consistently reaches 50% or higher, calculated based on the injection time of the corresponding water injection well, and the monthly water cut increase rate when the water cut of an oil well consistently reaches 50% or higher, calculated based on the water breakthrough time of the oil well. (Example:) Figure 3 As shown in Table 5, reservoir types are classified into reservoir classification intervals based on the data falling within the intervals.

[0096] Table 5 Reservoir Classification Intervals

[0097]

[0098] (5) For oil wells in the medium water cut stage (water cut stably reaches 50% or more) and with complete basic geological parameters of the reservoir:

[0099] Select the monthly water cut increase rate and production date data from oil and water well production data, the formation coefficient from basic reservoir geological parameters, and the injection-production well distance from well location data.

[0100] The monthly rate of increase in water cut when the water cut of an oil well stably reaches 50% or more is calculated based on the injection time of the corresponding water injection well: 50% / (date when the water cut of the oil well stably reaches 50% - date when the water cut of the corresponding water injection well is injected);

[0101] A water cut of 50% means that the water cut of the oil well has been stable at 50% or more for three consecutive months, with the date in months.

[0102] Establish a graph showing the relationship between the average formation coefficient / injection-production well distance ratio within the water injection drive distance and the monthly water cut increase rate calculated based on the water cut time of the oil well reaching a stable level of 50% and above. Figure 4As shown in Table 6, reservoir types are classified into reservoir classification intervals based on the data falling within the intervals.

[0103] Table 6 Reservoir Classification Intervals

[0104]

[0105] (6) For oil wells in the medium-to-high water cut stage (water cut stably reaches 75% or above):

[0106] Select the monthly water cut increase rate and oil / water well production date data from the oil and water well production data;

[0107] The monthly rate of increase in water cut when the oil well water cut stably reaches 75% or more is calculated based on the injection time of the corresponding water injection well: 75% / (date when the oil well water cut stably reaches 75% - corresponding injection date of the water injection well);

[0108] The monthly rate of increase in water cut, calculated based on the time it takes for the well to reach water, is: 75% / (date when the water cut of the well reaches 75% - date when the well is put into production).

[0109] A water cut of 75% means that the water cut of an oil well has remained stable at 75% or higher for three consecutive months, with the date in months.

[0110] A graph showing the relationship between the monthly rate of increase in water cut, where the water cut of an oil well consistently reaches 75% or higher, and the injection-production well spacing, is established based on the injection time of the corresponding water injection well. Figure 5a The graph shown below illustrates the relationship between the monthly rate of increase in water cut when the water cut of an oil well consistently reaches 75% or higher, and the distance between injection and production wells, calculated based on the oil well water injection time. Figure 5b As shown in the figure, and the relationship between the monthly water cut increase rate and the average formation coefficient / injection-production well spacing, calculated based on the time to water breakthrough of the oil well, when the water cut of the oil well is stably above 75%. Figure 6 As shown in Table 7, Table 8, and Table 9, reservoir types are divided into reservoir classification intervals based on the data falling into the intervals.

[0111] Table 7 Reservoir Classification Intervals

[0112]

[0113] Table 8 Reservoir Classification Intervals

[0114]

[0115] Table 9 Reservoir Classification Intervals

[0116]

[0117] (7) For dual-medium reservoirs:

[0118] Select the monthly average daily oil production, monthly average daily oil production decline rate, and oil well production date data in the oil-water well production data;

[0119] Since the decrease in fracture conductivity will cause the decrease in reservoir fluid production capacity, the absolute decrease range of monthly average daily oil production in the statistical period and the threshold interval of monthly average daily oil production decline rate in the statistical period are used to identify the fracture development section (the statistical period is selected as the time period in which the oil well can produce normally for two consecutive years). The relationship diagram of the absolute decrease range of monthly average daily oil production and the monthly average daily oil production decline rate in the statistical period is established, as shown in Figure 7 The reservoir type is divided into the reservoir classification interval shown in Table 10 according to the data falling into the interval;

[0120] Table 10 Reservoir classification interval

[0121]

[0122] (8) For dual medium reservoirs:

[0123] Select the monthly average daily oil production, monthly average daily oil production, and oil well production date data in the oil-water well production data;

[0124] Since the decrease in fracture conductivity will cause the decrease in reservoir fluid production capacity, the absolute decrease range of monthly average daily oil production in the statistical period and the threshold interval of monthly average daily oil production decline rate in the statistical period are used to identify the fracture development section (the statistical period is selected as the time period in which the oil well can produce normally for two consecutive years). The relationship diagram of the absolute decrease range of monthly average daily oil production and the monthly average daily oil production decline rate in the statistical period is established, as shown in Figure 8 The reservoir type is divided into the reservoir classification interval shown in Table 11 according to the data falling into the interval;

[0125] Table 11 Reservoir classification interval

[0126]

[0127] (9) In the case where the oil well working system is stable and the formation pressure is relatively stable:

[0128] Select the bottom hole flowing pressure, flow pressure unit pressure drop per meter oil production data in the oil-water well production data;

[0129] The relationship diagram of the absolute decrease range of the bottom hole flowing pressure and the per meter oil production of the flow pressure unit pressure drop under the stable working system is established, as shown in Figure 9 The reservoir type is divided into the reservoir classification interval shown in Table 12 according to the data falling into the interval;

[0130] Table 12 Reservoir classification interval

[0131]

[0132] The fractures between well groups in the reservoir were identified using the chart from Example 1: data from other well groups in the reservoir that had not undergone tracer testing and water breakthrough analysis were imported into the fracture identification chart from Example 1, and the fractures between well groups in the entire reservoir were identified based on the data falling within the pore type, fracture-pore type, and fracture type intervals.

[0133] Example 2: The 586 well group in this reservoir includes one water injection well (586 well) and four oil wells (790 well, 587 well, CT-24 well and H802 well) corresponding to its injection and production. The collected production data are shown in Table 13.

[0134] Table 13. Geological parameters and production data of well group 586

[0135]

[0136] Fractures were identified using a graph showing the relationship between the average formation coefficient / injection-production well spacing ratio and the water thrust velocity in the water breakthrough analysis data. The results are as follows: Figure 10 As shown. Based on the data falling within the specified range, the reservoir in well group 586 is a fracture-porosity type.

[0137] Example 3: The 543 well group in this reservoir includes one water injection well (543 well) and three oil wells (7615 well, 555 well and 7570 well) corresponding to its injection and production. The collected production data are shown in Table 14.

[0138] Table 14. Geological parameters and production data of well group 543.

[0139]

[0140] The average water cut of the wells in this well group is 54.4%, which is in the medium water cut stage. A graph showing the relationship between the monthly water cut increase rate (calculated based on the injection time of the corresponding injection well) and the monthly water cut increase rate (calculated based on the water breakthrough time) when the water cut consistently reaches 50% or higher was used. The data falling within the specified intervals indicates that this well group is a predominantly fractured and fracture-porosity area. Figure 11 As shown.

[0141] Example 4: The 516 well group in this reservoir includes two water injection wells (516 and 556). The oil production wells corresponding to well 516 are wells 7617, 195 and 758, and the oil production wells corresponding to well 556 are wells 515, 647, 784 and 7459. The collected production data are shown in Table 15.

[0142] Table 15. Geological parameters and production data of well group 586

[0143]

[0144] The average water content of the oil well of the well group is 82.4%, which is in a medium-high water content stage. The fracture is identified by using a month water content rising speed relation diagram of injection-production well group and the oil well water content stably reaching 75%, and the result is shown in Figure 12 、 Figure 13 According to the data falling into the interval, it is shown that the reservoir of the 516 well group is a pore type and no fracture is developed.

[0145] After statistical analysis of the fracture identification results of the main oil layer of the KT-II layer of the North Trova oil field in Kazakhstan in nearly one year, it is found that the overall coincidence rate of fracture identification by using the logging technology is 69.90%, while the overall coincidence rate of fracture identification by using the method of the present application is 90.85%(the overall coincidence rate is taken as the reference of the fracture identification results of the tracer test data and the water breakthrough analysis data), and 32 times of tracer test cost is saved in one year; at the same time, the injection scheme of 26 injection wells in the main area of the KT-II layer is adjusted, 0.6 million tons of oil is increased in one year, and the water content is reduced by 24.2%, which greatly improves the remaining oil displacement efficiency, and prevents the rapid advance of water injection.

[0146] Finally, it should be noted that the above content is only used to illustrate the technical solutions of the present application, and is not a limitation on the protection scope of the present application. Simple modifications or equivalent replacements of the technical solutions of the present application made by those skilled in the art do not deviate from the essence and scope of the technical solutions of the present application.

Claims

1. A method of producing dynamic data combined with test data to identify a crack, characterized by, Includes the following steps: Step 1: Collection of basic and production dynamic data of the oilfield: Collect basic and production dynamic data of injection-production well groups in the study area, including: basic geological parameters of the reservoir, production data of oil and water wells, well location data, tracer test data and water breakthrough analysis data; Step 2: Analyze reservoir type: Based on tracer test data and water breakage analysis data, the reservoir type was preliminarily classified. Step 3: Create a crack identification chart: Based on the preliminary classification of reservoir types, reservoir classification intervals are divided, and fracture identification charts are established; The crack identification diagram is at least one of the following eight relationship diagrams, specifically: ①: Relationship between average formation coefficient / injection-production well spacing and hydraulic thrust rate; ②: A graph showing the relationship between the monthly rate of increase in water cut when the water cut of an oil well reaches a stable level of 50%, calculated based on the injection time of the corresponding water injection well, and the monthly rate of increase in water cut when the water cut of an oil well reaches a stable level of 50% or higher, calculated based on the water breakthrough time of the oil well. ③: Relationship between average formation coefficient / injection-production well spacing and the monthly rate of increase in water cut when the water cut of the oil well reaches a stable level of 50% or more, calculated based on the time to water breakthrough. ④: Relationship between injection-production well spacing and the monthly rate of increase in water cut when the water cut of the oil well is consistently above 75%; ⑤: Relationship between average formation coefficient / injection-production well spacing and monthly water cut increase rate when water cut of water-bearing oil wells stably reaches 75% or more; ⑥: A graph showing the relationship between the absolute decrease in the average daily oil production of oil wells and the rate of decline in the average daily oil production of oil wells; ⑦: Relationship between the absolute decrease in monthly average daily fluid production and the absolute decrease in monthly average daily oil production; ⑧: Relationship between the absolute decrease in bottom hole flowing pressure and the oil production per unit pressure drop per meter; Step 4: Identify cracks: The basic and production dynamic data of the injection-production well groups in the study area are imported into the fracture identification chart, and the fractures between well groups are identified according to the reservoir type range in which the data falls.

2. The method of claim 1, wherein, The basic geological parameters of the reservoir are one or more of the following: formation coefficient, permeability, and reservoir thickness.

3. The method of claim 1, wherein, The oil and water well production data includes one or more of the following: monthly water cut increase rate, oil and water well production date, monthly average daily fluid production, monthly average daily oil production, daily oil production decline rate, bottom hole flowing pressure, and oil production per meter of flowing pressure unit pressure drop.

4. The method of claim 1, wherein, The well location data includes one or both of the well location coordinates and the injection-production well distance.

5. The method of claim 1, wherein, The tracer test data is the water drive velocity.

6. The method of claim 1, wherein, The water breakthrough analysis data includes the water thrust rate and the injection-production well spacing.

7. The method of claim 1, wherein, In step two, the reservoir types include three types: porous, fracture-porous, and fractured.

8. The method of claim 1, wherein, In step four, the basic and production dynamic data of the injection-production well group in the study area are one or more of the following: basic geological parameters of the reservoir, production data of oil and water wells, and well location data.

9. The method of claim 1, wherein, The crack identification chart also includes: ⑨ Relationship between water drive rate and injection-production well spacing; And / or ⑩ Relationship between water thrust rate and injection-production well spacing.

10. The method of claim 9, wherein, It also includes: verifying the fracture identification results using the relationship diagrams between the water drive velocity and the injection-production well spacing and the water thrust velocity and the injection-production well spacing.

11. A crack identification plate for use in the method of any one of claims 1-10.

12. The application of the fracture identification chart according to claim 11 in reservoir fracture identification.

13. Use according to claim 12, characterized in that, The reservoirs include conventional reservoirs, medium water cut stage reservoirs with water cut of water breakthrough wells being 50% or more, medium-high water cut stage reservoirs with water cut of water breakthrough wells being 75% or more, and dual media reservoirs.

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