Fracture control fracture-cavity type carbonate reservoir refracturing well selection and layer selection method and application

Abstract

The invention relates to a fracture-control fracture-cavity type carbonate reservoir refracturing well and layer selecting method and application, and belongs to the technical field of oil and gas field yield increasing. The method comprises the following steps that reservoir data, production dynamic data and primary fracturing data of all oil wells in a work area are obtained; determining candidate reconstruction wells according to the oil production level threshold value of each oil well in the current work area; according to the initial oil production level and the half-year declining rate cross plot, determining an original fracture re-pressing potential well and a layer-changing heavy-pressing potential well in the candidate reconstruction wells; according to the cross plot of the water production level and the current water content of each oil well in the work area and / or the cross plot of the well control effective fracture-cavity volume and the initial pressure production rate, determining an original fracture re-pressing target well and / or a layer-changing heavy-pressing target well; the invention further provides application of the method in oil and gas well fracturing. Compared with the prior art, the fracturing well selection and layer selection method is simple, parameters are easy to obtain, and the fracturing well selection and layer selection method can be applied to different blocks.

Description

Technical Field

[0001] The present invention belongs to the technical field of enhanced oil and gas recovery in oil and gas fields, and particularly relates to a method and application for well and layer selection of refracturing in fractured-vuggy carbonate reservoirs controlled by faults. Background Technique

[0002] The oil and gas resources in the Shunbei area are characterized by large reserves, good quality, and great development potential. The oil and gas resources in this area are mainly concentrated in carbonate rocks, with high abundance and grade. In addition, this area also has good development conditions and infrastructure, providing convenience for oil and gas development. At present, through the comprehensive analysis of the tectonic evolution, reservoir, oil and gas reservoir characteristics, and oil and gas enrichment laws of the ultra-deep oil and gas fields in Shunbei, it is considered that this type of oil and gas reservoir is a fractured-vuggy carbonate oil and gas reservoir controlled by faults, with the characteristics of overall oil-bearing along the fault zone and uneven enrichment. After the initial fracturing of the oil wells in the Shunbei area, the production capacity generally drops rapidly, and many wells face low production or shut-in due to blowout cessation. The production capacity can be restored and the recovery rate of the oil wells can be improved through refracturing.

[0003] Patent application CN113719265A discloses a method, device, and equipment for well selection of refracturing in horizontal shale oil wells; the method includes obtaining the oil production level before cross-interference and the oil production during cross-interference of each horizontal well in the horizontal well group to be selected, and calculating the cross-interference affected production of each horizontal well; calculating a comprehensive index including the reverse percentile of the cross-interference degree of each horizontal well according to the production indexes of each horizontal well including the cross-interference affected production; and selecting the horizontal wells that can perform refracturing calculation according to the comprehensive indexes of each horizontal well and a set threshold. The method of the present invention considers the influence of cross-interference between wells on well selection, can select the horizontal wells that can perform refracturing calculation in the horizontal well group to be selected, improves the well selection accuracy, and reduces the workload of performing refracturing calculation on the horizontal well group to be selected.

[0004] However, the oil reservoirs in the Shunbei area have a large burial depth, special reservoir types, and it is difficult to obtain reservoir data. The number of samples of refractured well layers that have been implemented is small. At present, the well selection methods for refracturing in shale reservoirs, tight gas reservoirs, coalbed methane reservoirs, etc. are not applicable to the ultra-deep fractured-vuggy carbonate reservoirs controlled by faults in the Shunbei area.

[0005] Patent application CN112983377A discloses a method for evaluating the potential of refracturing and selecting wells for enhanced production in vertical wells in low-permeability reservoirs, including the following steps: taking the previously fractured wells as candidate wells, and collecting the basic information of the candidate wells, where the basic information includes reservoir information, fracturing information, and production performance information; constructing a virtual target well with the potential for refracturing and enhanced production; calculating the correlation coefficient between the candidate wells and the virtual target well; and evaluating the potential of refracturing and enhanced production of the candidate wells based on the correlation coefficient. The invention comprehensively considers the influence of reservoir, fracturing, and production performance information on the effect of refracturing and enhanced production, and can more accurately quantitatively evaluate the potential of refracturing and enhanced production in vertical wells in low-permeability reservoirs; however, the prerequisite for this method is that a considerable number of wells have been refractured and the production effect after refracturing can be obtained. Since the sample of refractured well layers in the Shunbei area is small, the method provided by the invention requires many basic parameters for well and layer selection, and some parameters are not easy to obtain, so it is difficult to draw on to solve the oil and gas exploitation problems in the Shunbei area.

[0006] Therefore, how to provide a method for selecting wells and layers for reservoir refracturing that can be applied to fault-controlled fracture-cavity carbonate oil and gas reservoirs and improve the resource development efficiency of oil and gas reservoirs is one of the key issues studied by those skilled in the art. Summary of the Invention

[0007] Aiming at the lack of a method for selecting wells and layers for reservoir refracturing applicable to fault-controlled fracture-cavity carbonate oil and gas reservoirs in the prior art, the present invention provides a method for selecting wells and layers for reservoir refracturing in fault-controlled fracture-cavity carbonate reservoirs, which can quickly and effectively select target well layers with the potential for refracturing, providing a basis for the design of refracturing plans.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] A method for selecting wells and layers for reservoir refracturing in fault-controlled fracture-cavity carbonate reservoirs, including the following steps:

[0010] S1. Obtain the reservoir information, production performance information, and primary fracturing information of each oil well in the work area;

[0011] S2. Determine the candidate wells for transformation according to the oil production level threshold of each oil well in the work area at present;

[0012] S3. Determine the wells with the potential for refracturing the original fractures and the wells with the potential for heavy fracturing of modified layers among the candidate wells for transformation in step S2 according to the cross-plot of the initial oil production level and the half-year decline rate;

[0013] S4. Determine the target wells for refracting the original fractures and / or the target wells for heavy fracturing of modified layers according to the cross-plot of the water production level and the current water cut of each oil well in the work area and / or the cross-plot of the effectively controlled fracture-cavity volume by the well and the initial fracturing utilization rate.

[0014] The determination of the original seam recompression target well and / or the modified layer heavy pressure target well is the result of well selection and layer selection.

[0015] Preferably, the reservoir data, production dynamic data, and primary fracturing data in step S1 include the current oil production level, current water production level, current water cut, initial oil production level, half-year decline rate, effective fracture-cavity volume controlled by the well, and primary fracturing utilization rate.

[0016] Preferably, the oil production level threshold in step S2 is: the lower limit value of the current single-well economic daily production.

[0017] Preferably, the criterion for determining the candidate wells in step S2 is: oil wells with a current production level lower than the current oil production level threshold.

[0018] Preferably, the method for determining the original seam recompression potential wells and the modified layer heavy pressure potential wells in step S3 includes the following steps:

[0019] Taking the candidate reconstruction wells with an initial oil production level greater than the initial oil production level threshold and a half-year decline rate less than the half-year decline rate threshold as the original seam recompression potential wells;

[0020] Taking the candidate reconstruction wells with an initial oil production level less than the initial oil production level threshold as the modified layer heavy pressure potential wells.

[0021] More preferably, the value of the initial oil production level threshold is 30-50% of the maximum value of the initial oil production level of the candidate reconstruction wells.

[0022] Even more preferably, the value of the half-year decline rate threshold is 40-60% of the maximum value of the half-year decline rate threshold of the candidate reconstruction wells.

[0023] Preferably, the method for determining the original seam recompression target wells in step S4 includes the following steps:

[0024] Taking the original seam recompression potential wells with a current water production level less than the current water production level threshold and a current water cut less than the current water cut threshold as the original seam recompression target wells.

[0025] More preferably, the value of the current water production level threshold is: 30-50% of the maximum value of the current water production level of the candidate reconstruction wells.

[0026] Even more preferably, the value of the current water cut threshold is: 40-60% of the maximum value of the current water cut of the candidate reconstruction wells.

[0027] Preferably, the method for determining the modified layer heavy pressure target wells in step S4 includes the following steps:

[0028] Take the potential wells for re - fracturing in the modified layer with the effective fracture - cave volume for well control greater than the threshold value of the effective fracture - cave volume for well control and the initial pressure utilization rate less than the threshold value of the initial pressure utilization rate as the target wells for re - fracturing in the modified layer.

[0029] Further preferably, the value of the threshold of the effective fracture - cave volume for well control is: 30 - 50% of the maximum value of the effective fracture - cave volume for well control of the candidate wells for stimulation.

[0030] Even more preferably, the value of the threshold of the initial pressure utilization rate is: 40 - 60% of the maximum value of the initial pressure utilization rate of the candidate wells for stimulation.

[0031] The present invention also provides an application of the method for selecting wells and layers for refracturing in fractured - vuggy carbonate reservoirs with fault control in the fracturing of oil and gas wells.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The present invention uses the analytic hierarchy process and cross - plot method, comprehensively considering geological, reservoir and engineering factors, and can quickly and effectively screen out the potential well sections that are not thoroughly stimulated in the primary fracturing or not utilized in the primary fracturing, namely the potential wells for re - fracturing of the original fractures and the potential wells for re - fracturing in the modified layer, providing a basis for the design of the refracturing plan. The method for selecting wells and layers for fracturing provided by the present invention is simple, and the parameters are easy to obtain, and can be applied to different blocks. Brief Description of the Drawings

[0034] Figure 1 It is a flow chart of a method for selecting wells and layers for refracturing in fractured - vuggy carbonate reservoirs with fault control shown in the embodiment of the present invention;

[0035] Figure 2 It is a statistical histogram of the current production level of oil wells in the Shunbei No. 5 fault zone shown in the embodiment of the present invention;

[0036] Figure 3 It is a cross - plot of the initial production capacity and the half - year decline rate of candidate wells for stimulation in the Shunbei No. 5 fault zone shown in the embodiment of the present invention;

[0037] Figure 4 It is a cross - plot of the current water production level and the current water cut of candidate wells for stimulation in the Shunbei No. 5 fault zone shown in the embodiment of the present invention;

[0038] Figure 5 It is a cross - plot of the effective fracture - cave volume for well control and the initial pressure utilization rate of candidate wells for stimulation in the Shunbei No. 5 fault zone shown in the embodiment of the present invention. Detailed Embodiments

[0039] The present invention will now be described more fully with reference to the accompanying drawings. However, the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the present invention to those skilled in the art.

[0040] The flowcharts shown in the accompanying drawings are merely illustrative and not necessarily inclusive of all contents and steps, nor are they necessarily to be executed in the described order. For example, some steps can be decomposed, while some steps can be combined or partially combined, so the actual execution order may change according to the actual situation.

[0041] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0042] Embodiment A method for selecting wells and layers for refracturing of fracture-controlled vuggy carbonate reservoirs

[0043] Figure 1 The flowchart of the method for selecting wells and layers for refracturing of fracture-controlled vuggy carbonate reservoirs according to an embodiment of the present invention is shown.

[0044] Refer to Figure 1 , the method for selecting wells and layers for refracturing of fracture-controlled vuggy carbonate reservoirs provided by the embodiment of the present invention may include the following steps:

[0045] Step S1: Obtain the reservoir, production performance, and primary fracturing data of the oil well, including the current oil production level, current water production level, current water cut, initial oil production level, half-year decline rate, effectively controlled fracture-vug volume by the well, and primary fracturing utilization rate.

[0046] The following will take the target well as an example to explain how to obtain the reservoir, production performance, and primary fracturing data of an oil well:

[0047] Current oil production level q , ,

[0048] , w,目前 , o,目前 , , ,

[0049] , o,t-i , , o,目前 ,

[0052] , ,

[0051] ,

[0050] : Refer to formula (1), the daily oil production of the target well in the most recent n days can be obtained, where n is an integer greater than or equal to 1; average the daily oil production in the most recent n days to determine the current oil production level q of the target well o,目前 .

[0048]

[0049] In the formula:

[0050] q o,t-i is the daily oil production i days ago, t / d;

[0051] n is the time, d, and generally takes a value of 90.

[0052] Current water production level q w,目前Referring to Equation (2), the daily water production of the target well in the most recent n days can be obtained, where n is an integer greater than or equal to 1; the daily water production in the most recent n days is averaged to determine the current water production level q of the target well. w,目前 。

[0053]

[0054] Where:

[0055] q w,t-i is the daily water production i days ago, m 3 / d;

[0056] n is the time, d, and generally takes a value of 90.

[0057] The current water cut f w,目前 : Referring to Equation (3), the daily water cut of the target well in the most recent n days can be obtained, where n is an integer greater than or equal to 1; the daily water cut in the most recent n days is averaged to determine the current water cut f of the target well. w,目前 。

[0058]

[0059] Where:

[0060] f w,t-i is the daily water cut i days ago, %;

[0061] n is the time, d, and generally takes a value of 90.

[0062] The initial oil production level q o,初期 : Referring to Equation (4), the daily oil production of the target well in the m days before production after the first fracturing can be obtained, where m is an integer greater than or equal to 1; the daily oil production in the first m days is averaged to determine the initial oil production level q of the target well. o,初期 。

[0063]

[0064] Where:

[0065] q o,i is the daily oil production on the i-th day after production after the first fracturing, t / d;

[0066] m is the time, d, and generally takes a value of 30.

[0067] The six-month decline rate D: Referring to Equation (5), the average daily oil production of the target well in the 7th month after production after the first fracturing can be obtained as the six-month oil production level q of the target well. o,半年 ; Referring to Equation (6), the initial oil production level q of the target well o,初期 and the six-month oil production level q o,半年Calculate the difference and compare it with the initial oil production level q o,初期 Take the ratio as the six - month decline rate of the target well.

[0068]

[0069]

[0070] In the formula:

[0071] is the daily oil production on the i - th day of the 7th month after the initial fracturing and production, t / d;

[0072] k is a constant, generally taking the value of 180;

[0073] m is time, d, generally taking the value of 30.

[0074] Initial fracturing utilization rate U: Refer to formula (6), and take the ratio of the initial fracturing volume V 初压 to the volume V of the effective fracture - cavity reservoir body controlled by the well 井控 as the initial fracturing utilization rate U of the target well.

[0075]

[0076] In the formula:

[0077] V 初压 is the initial fracturing volume, 10 4 m 3 ;

[0078] V 井控 is the volume of the effective fracture - cavity reservoir body controlled by the well, 10 4 m 3 .

[0079] Those skilled in the art can determine the reservoir, production dynamics, and initial fracturing data of other oil wells by referring to the determination methods of the reservoir, production dynamics, and initial fracturing data of the target well.

[0080] Step S2, determine the candidate wells for transformation according to the current oil production level threshold.

[0081] In some embodiments, the current production level threshold is generally determined according to the lower limit of the single - well economic daily production in the study area, such as 50 t / d.

[0082] In some embodiments, the oil wells with the current production level lower than the current production level threshold can be used as candidate wells for transformation.

[0083] In some embodiments, the oil wells with the current production level higher than or equal to the current production level threshold can be allowed to continue production without transformation.

[0084] Step S3: Determine the potential wells for original fracture recompression and the potential wells for layer modification and heavy pressure according to the intersection diagram of initial oil production level and six - month decline rate.

[0085] In some embodiments, first determine the initial oil production level threshold and the six - month decline rate threshold. The initial oil production level threshold is generally taken as 30 - 50% of the maximum initial oil production level of the candidate wells for transformation, and the six - month decline rate threshold is generally taken as 40 - 60% of the maximum six - month decline rate of the candidate wells for transformation.

[0086] In some embodiments, take the candidate wells for transformation with an initial oil production level greater than the initial oil production level threshold and a six - month decline rate less than the six - month decline rate threshold as the potential wells for original fracture recompression.

[0087] In some embodiments, take the candidate wells for transformation with an initial oil production level less than the initial oil production level threshold as the potential wells for layer modification and heavy pressure.

[0088] Step S4: Determine the target wells for original fracture recompression among the potential wells for original fracture recompression according to the intersection diagram of current water production level and current water cut.

[0089] In some embodiments, first determine the current water production level threshold and the current water cut threshold. The current water production level threshold is generally taken as 30 - 50% of the maximum current water production level of the candidate wells for transformation, and the current water cut threshold is generally taken as 40 - 60% of the maximum current water cut of the candidate wells for transformation.

[0090] In some embodiments, take the potential wells for original fracture recompression with a current water production level less than the current water production level threshold and a current water cut less than the current water cut threshold as the target wells for original fracture recompression.

[0091] Determine the target wells for layer modification and heavy pressure among the potential wells for layer modification and heavy pressure according to the intersection diagram of effectively controlled fracture - cave volume and initial pressure utilization rate.

[0092] In some embodiments, determine the effectively controlled fracture - cave volume threshold and the initial pressure utilization rate threshold. The effectively controlled fracture - cave volume threshold is generally taken as 30 - 50% of the maximum effectively controlled fracture - cave volume of the candidate wells for transformation, and the initial pressure utilization rate is generally taken as 40 - 60% of the maximum initial pressure utilization rate of the candidate wells for transformation.

[0093] In some embodiments, take the potential wells for layer modification and heavy pressure with an effectively controlled fracture - cave volume greater than the effectively controlled fracture - cave volume threshold and an initial pressure utilization rate less than the initial pressure utilization rate threshold as the target wells for layer modification and heavy pressure.

[0094] The method for well selection and layer selection of refracturing in the No. 5 fracture zone of Shunbei oilfield may include the following steps:

[0095] The first step: Determine the candidate wells for transformation. Screen out the low - production wells and the shut - in wells as the candidate wells for transformation according to the current oil production level histogram, and set the current oil production level threshold to 50 t / d.

[0096] The current oil production level reflects the current production status of the oil well. A high current oil production level indicates that the current production status of the oil well is good and no other measures are required. A low or zero current oil production level indicates that the oil well is in a low-production state or a shut-in state, and a feasibility analysis of heavy fracturing is needed.

[0097] Figure 2 It is a statistical histogram of the current production levels of the oil wells in the Shunbei No. 5 fault zone shown according to an exemplary embodiment.

[0098] Reference Figure 2 Shown in the illustrated embodiment, there are 5 wells in the Shunbei No. 5 fault zone with a current oil production level greater than 50 t / d, and the production situation is good, and repeated reconstruction is not appropriate; the current production levels of 3 wells are less than 25 t / d, in a low-production state, and 6 wells are in a shut-in state. Therefore, 9 wells in the low-production state and the shut-in state are selected as candidate reconstruction wells.

[0099] Step 2: Determine the potential reconstruction wells and classify them. According to the initial oil production level and the six-month decline rate, determine the potential wells for re-fracturing the original fractures and the potential wells for heavy fracturing of the modified layers. Wells with a high initial oil production level (>50 t / d) and a slow decline (<60%) are used as potential wells for re-fracturing the original fractures; wells with a low initial oil production level (<50 t / d) are used as potential wells for heavy fracturing of the modified layers.

[0100] The initial oil production level reflects the initial oil production capacity of the oil well and the effect of the first fracturing.

[0101] The six-month decline rate reflects the oil supply capacity of the reservoir.

[0102] Figure 3 It is a crossplot of the initial production capacity and the six-month decline rate of the candidate reconstruction wells in the Shunbei No. 5 fault zone shown according to an exemplary embodiment.

[0103] Step 3: Determine the target wells for re-fracturing the original fractures. For the potential wells for re-fracturing the original fractures, select wells with a low current water production level (<20 m 3 / d) and a low current water cut (<60%) as the target wells for re-fracturing the original fractures.

[0104] At the initial stage of oil well production, there is basically no water or the water cut is extremely low. If the water cut increases after adjustment according to production measures such as pumping for low-pressure wells and water injection for shut-in wells, careful consideration is needed and repeated reconstruction should be avoided as much as possible. Therefore, when selecting wells and layers for repeated fracturing, wells with a low current water production level and a low current water cut should be selected as the target wells for re-fracturing the original fractures.

[0105] Figure 4 It is a crossplot of the current water production level and the current water cut of the candidate reconstruction wells in the Shunbei No. 5 fault zone shown according to an exemplary embodiment.

[0106] Step 4: Determine the target wells for re - fracturing in the modified layer. Among the potential wells for re - fracturing in the modified layer, select wells with a large effective fracture - cavity volume for well control (>1000×10 4 m 3 ) and a low utilization rate (<60%) as the target wells for re - fracturing in the modified layer.

[0107] If the effective fracture - cavity volume for well control is large but the utilization rate is low, it indicates that there are other potential fracture - cavity reservoirs around the well that have not been utilized, and these reservoirs can be connected through refracturing.

[0108] Figure 5 It is the cross - plot of the effective fracture - cavity volume for well control and the initial pressure utilization rate of the candidate stimulation wells in the Shunbei No. 5 fault zone shown according to the exemplary embodiment.

[0109] Based on the current oil production level, the initial oil production level, the half - year decline rate, the current water production level and the current water cut, the effective fracture - cavity volume for well control and the initial pressure utilization rate, finally, 3 refracturing target wells are selected ( Figure 4 and 5 the boxed part in).

[0110] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the embodiments of the present invention. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include known common general knowledge or conventional technical means in the technical field of the present invention that are not claimed in the present application. The specification and embodiments are only to be considered as exemplary, and the true scope and spirit of the present invention are pointed out by the claims.

[0111] It should be understood that the present invention is not limited to the detailed structures, drawing methods, or implementation methods shown here. On the contrary, the present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[0112] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than a limitation on the protection scope of the present invention. Any simple modification or equivalent replacement made by those of ordinary skill in the art to the technical solution of the present invention does not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs, characterized in that It includes the following steps: S1. Obtain the reservoir data, production performance data, and primary fracturing data of each oil well in the work area; S2. Determine the candidate wells for reconstruction according to the oil production level threshold of each oil well in the current work area; S3. Determine the potential wells for re-fracturing the original fractures and the potential wells for re-fracturing the modified layers among the candidate wells for reconstruction described in step S2 according to the cross-plot of the initial oil production level and the half-year decline rate; S4. Determine the target wells for re-fracturing the original fractures and / or the target wells for re-fracturing the modified layers according to the cross-plot of the water production level and the current water cut of each oil well in the work area and / or the cross-plot of the effectively controlled fracture-cavity volume and the primary fracturing utilization rate.

2. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 1, wherein The reservoir data, production performance data, and primary fracturing data described in step S1 include the current oil production level, the current water production level, the current water cut, the initial oil production level, the half-year decline rate, the effectively controlled fracture-cavity volume, and the primary fracturing utilization rate.

3. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 1, characterized in that, The oil production level threshold described in step S2 is: the lower limit value of the current single-well economic daily oil production.

4. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 1, wherein The criterion for determining the candidate wells described in step S2 is: the oil wells with the current production level lower than the current oil production level threshold.

5. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 1, characterized in that, The method for determining the potential wells for re-fracturing the original fractures and the potential wells for re-fracturing the modified layers described in step S3 includes the following steps: Take the candidate wells for reconstruction with the initial oil production level greater than the initial oil production level threshold and the half-year decline rate less than the half-year decline rate threshold as the potential wells for re-fracturing the original fractures; Take the candidate wells for reconstruction with the initial oil production level less than the initial oil production level threshold as the potential wells for re-fracturing the modified layers.

6. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 5, characterized in that The value of the initial oil production level threshold is 30-50% of the maximum value of the initial oil production level of the candidate wells for reconstruction.

7. The method for selecting wells and intervals for refracturing of fractured-vuggy carbonate reservoirs according to claim 5, characterized in that, The value of the half-year decline rate threshold is 40-60% of the maximum value of the half-year decline rate threshold of the candidate wells for reconstruction.

8. The method for selecting wells and layers for refracturing of fractured-vuggy carbonate reservoirs according to claim 1, characterized in that The method for determining the target wells for re-fracturing the modified layers described in step S4 includes the following steps: Take the potential wells for re-fracturing the modified layers with the effectively controlled fracture-cavity volume greater than the effectively controlled fracture-cavity volume threshold and the primary fracturing utilization rate less than the primary fracturing utilization rate threshold as the target wells for re-fracturing the modified layers.

9. The method for selecting wells and layers for refracturing of a fault-controlled fracture-cavity type carbonate reservoir according to claim 8, characterized in that The value of the effectively controlled fracture-cavity volume threshold is: 30-50% of the maximum value of the effectively controlled fracture-cavity volume of the candidate wells for reconstruction.

10. The method for selecting wells and layers for refracturing of a fault-controlled fracture-cavity type carbonate reservoir according to claim 8, characterized in that The value of the primary fracturing utilization rate threshold is: 40-60% of the maximum value of the primary fracturing utilization rate of the candidate wells for reconstruction.

11. The application of the method for selecting wells and layers for refracturing of a fault-controlled fracture-cavity type carbonate reservoir according to any one of claims 1-10 in the fracturing of oil and gas wells.

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