Well group fracturing crosstalk real-time treatment method

Abstract

The invention relates to the technical field of fracturing tampering treatment methods, in particular to a well group fracturing tampering real-time treatment method which comprises the steps that in the fracturing process, the fracture extension form of a fractured well is monitored in real time through underground microseism, and pressure of an adjacent well of the fractured well is monitored in real time so as to determine the crosstalk type of the fractured well; determining the usage amount of a temporary plugging agent according to the crosstalk type of the fractured well; performing crosstalk treatment by using the determined use amount of the temporary plugging agent; and after crosstalk treatment, whether crosstalk treatment is effective or not is determined according to the pressure change of the adjacent well and the fracture extension form. The pressure real-time monitoring technology, the underground micro-earthquake real-time monitoring technology and the in-fracture temporary plugging treatment crosstalk technology are integrated, a set of process of adjacent well real-time pressure monitoring, underground micro-earthquake real-time monitoring and temporary plugging treatment crosstalk is formed, the crosstalk influence is effectively reduced, and the effects of fully transforming a new well, improving the yield and reducing the yield reduction of an old well due to crosstalk are achieved.

Description

Technical Field

[0001] This invention relates to the technical field of fracturing crosstalk control methods, and is a real-time control method for fracturing crosstalk in well groups. Background Technology

[0002] Hydraulic fracturing is a crucial production enhancement measure for oil and gas wells, water injection wells, and overall oil and gas well productivity and recovery. Hydraulic fracturing involves injecting high-viscosity fracturing fluid, exceeding the formation's absorption capacity, into the well using a high-pressure pump truck. This creates high pressure near the wellbore. When the pressure exceeds the geostress and the tensile strength of the rock, fractures form in the formation. Further fracturing fluid containing proppant is injected into the fractures, which extend and are filled with proppant. After pumping stops, the fracturing fluid breaks down and flows back, while the proppant remains in the fractures. This results in sufficiently long, wide, and high-conductivity sand-filled fractures in the formation, increasing the permeability of the oil and gas reservoir and boosting oil and gas well production.

[0003] Low-porosity and low-permeability reservoirs in Xinjiang Oilfield require hydraulic fracturing to achieve production capacity. However, crosstalk during fracturing is a significant problem, affecting the effectiveness of new well stimulation and the production of older wells. Therefore, identifying crosstalk and reducing or eliminating it are urgent challenges that need to be addressed.

[0004] Mahu is an important part of the production of Xinjiang Oilfield. The problem of cross-contamination during production at the Mahu site has been frequently encountered. In 2022, 85 wells, both new and old, were affected by cross-contamination during production. The old wells were affected by a production loss of 132,800 tons. The problems of insufficient fracturing and transformation of new wells and difficulty in reaching production levels, as well as the impact of cross-contamination on production from old wells, urgently need to be addressed and resolved. Summary of the Invention

[0005] This invention provides a real-time management method for crosstalk during fracturing of well groups, which overcomes the shortcomings of the prior art. It can detect crosstalk between wells and between layers in a timely manner, and reduce the impact of crosstalk by temporary plugging, so as to fully improve new wells and reduce the production reduction of old wells due to crosstalk.

[0006] The technical solution of this invention is achieved through the following measures: a real-time control method for well group fracturing interference, comprising: During the fracturing process, downhole microseismic monitoring is used to monitor the fracture extension morphology of the fracturing well in real time, and pressure monitoring is performed on adjacent wells in real time to determine the crosstalk type of the fracturing well. Crosstalk types in fractured wells include one or more of the following: inter-well crosstalk and crosstalk between well classes.

[0007] The amount of temporary plugging agent to be used is determined based on the type of crosstalk in the fracturing well; Crosstalk is controlled using the determined amount of temporary plugging agent. After crosstalk mitigation, the effectiveness of the mitigation is determined by the pressure changes in adjacent wells and the fracture extension morphology.

[0008] For crosstalk between wells, after crosstalk treatment, the effectiveness of the treatment is determined by the pressure changes in adjacent wells and the fracture extension morphology. For example, if the pressure in adjacent wells continues to rise without any signs of slowing down after temporary plugging with a plugging agent, and the fracture length continues to extend abnormally, it indicates that the crosstalk treatment is ineffective. Therefore, a second temporary plugging within the fracture is carried out, with the amount of plugging agent used being 150% of the first amount. For crosstalk between the same well level, such as when the fractures in the well continue to cross level after temporary plugging with a plugging agent, it indicates that the crosstalk control is ineffective. Therefore, a second temporary plugging is carried out within the fracture, and the amount of plugging agent used is 150% of the first one.

[0009] The following are further optimizations and / or improvements to the above-mentioned technical solution: Furthermore, when the crosstalk type of the fractured well is inter-well crosstalk, the pressure of the adjacent well of the fractured well rises (the rise value is ≥1MPa), and the artificial fractures of the fractured well extend to the adjacent well of the fractured well.

[0010] After the treatment, the pressure rise in the adjacent well slowed down, indicating that the treatment was effective.

[0011] Furthermore, when the crosstalk type of the fractured well is inter-well crosstalk, the pressure of at least one adjacent well of the fractured well increases.

[0012] Furthermore, when the crosstalk type of the fractured well is inter-well class crosstalk, the inter-well class crosstalk level is one level or higher.

[0013] Furthermore, when using downhole microseismic real-time monitoring of the fracture extension morphology in a fractured well, the parameters of the microseismic real-time monitoring include at least the width, length, and height of the fracture.

[0014] This invention integrates real-time pressure monitoring technology, downhole microseismic real-time monitoring technology, and fracture temporary plugging technology to control crosstalk, forming a complete process of real-time pressure monitoring of adjacent wells, real-time downhole microseismic monitoring, and temporary plugging to control crosstalk. This effectively reduces the impact of crosstalk, achieving the effect of fully modifying new wells to increase production and reducing the production reduction of old wells due to crosstalk. It has strong market competitiveness and broad application prospects. Attached Figure Description

[0015] Appendix Figure 1 This is the technical approach of the present invention.

[0016] Appendix Figure 2 This is a map of downhole microseismic monitoring.

[0017] Appendix Figure 3 The amount of sand for a single joint is 35m. 3 Simulated image of crack morphology.

[0018] Appendix Figure 4 This is a real-time monitoring graph of well pressure for fractured well B and monitoring well C.

[0019] Appendix Figure 2 In the diagram, green spheres and red spheres represent monitoring vibration points for real-time downhole microseismic monitoring. Green spheres represent monitoring vibration points before temporary plugging, while red spheres represent monitoring vibration points after temporary plugging. Detailed Implementation

[0020] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0021] The present invention will be further described below with reference to embodiments: Example 1: As shown in the attached document Figure 1 As shown, the real-time control method for fracturing disturbance in this well group includes: During the fracturing process, downhole microseismic monitoring is used to monitor the fracture extension morphology of the fracturing well in real time, and pressure monitoring is performed on adjacent wells in real time to determine the crosstalk type of the fracturing well. The amount of temporary plugging agent to be used is determined based on the type of crosstalk in the fracturing well; Crosstalk is controlled using the determined amount of temporary plugging agent. After crosstalk mitigation, the effectiveness of the mitigation is determined by the pressure changes in adjacent wells and the fracture extension morphology.

[0022] Downhole microseismic real-time monitoring is a conventional monitoring technology that involves placing geophones in fractured wells or other monitoring wells for monitoring.

[0023] Example 2: As an optimization of Example 1, the crosstalk type of the fractured well includes one or more of the following: inter-well crosstalk and inter-well class crosstalk.

[0024] Example 3: As an optimization of Example 2, when the crosstalk type of the fractured well is inter-well crosstalk, the pressure of the adjacent well of the fractured well rises, and the artificial fracture extends to the adjacent well of the fractured well. At this time, the fracture extension is judged to be abnormal.

[0025] Example 4: As an optimization of Example 3, when the crosstalk type of the fractured well is inter-well crosstalk, the pressure of at least one adjacent well of the fractured well increases.

[0026] Example 5: As an optimization of Example 2, when the crosstalk type of the fractured well is inter-well level crosstalk, the inter-well level crosstalk level is one or more.

[0027] When crosstalk occurs between different well levels, it means that the artificial fracture extends to the corresponding location of other fracturing layers. In this case, the fracture extension is considered abnormal.

[0028] Example 6: As an optimization of Example 1, when using downhole microseismic real-time monitoring of the fracture extension morphology of a fractured well, the parameters of the microseismic real-time monitoring include at least the width, length and height of the fracture.

[0029] The real-time control method for crosstalk in well cluster fracturing described in this invention has been applied in 10 wells, totaling 126 levels. Among them, crosstalk between wells of the same level reached level 8. The crosstalk control through temporary plugging achieved an effectiveness rate of 100%, demonstrating good practicality.

[0030] The following explanation uses examples 1 to 3 as examples.

[0031] Application Example 1: Inter-well crosstalk control Well A, Level 14, employs a combination of downhole microseismic real-time monitoring and in-fracture temporary plugging technology. Step 1: Real-time downhole microseismic monitoring revealed abnormal expansion of the level 14 fracture in Well A (artificial fracture length exceeding normal fracture length by ≥10%), intra-fracture crosstalk, and distal fractures connecting to level 13 fractures. (See...) Figure 2 (Before the temporary blockage, the green sphere corresponding to the level 14 crack appeared in the level 13 crack, indicating that the level 14 crack is connected to the level 13 crack at a distant end.)

[0032] Step 2: Stop the pump and calculate the amount of temporary plugging agent to be added based on the real-time microseismic monitoring results, as shown in Table 1: m = 2 × H × L × W × ρ m: dosage of temporary plugging agent, kg H: Monitoring crack height (crack network height), m L: Temporary clogging depth (valued at 0.15 here), m W: Crack width (valued at 0.011 here, obtained through simulation), m ρ: Density of temporary plugging agent, kg / m³ 3 m=2×(25+21)×0.15×0.011×1.3×10 3 =197.34kg.

[0033] Step 3: After restarting the pump, add 200 kg of 1mm to 3mm powdered temporary plugging agent (conventional oil-soluble temporary plugging agent, the same below). Real-time monitoring via downhole microseismic testing showed that the extension of the level 14 fracture was normal, indicating effective treatment within the fracture. See [link to article]. Figure 2 (After the temporary blockage, the red sphere corresponding to the level 14 crack enters the level 13 crack and fills the crack between level 14 and level 13).

[0034] Step 4: Real-time monitoring of the artificial fracture length via downhole microseismic monitoring shows it continues to extend abnormally; stop the pump and add 1.5 kg of 1 mm to 3 mm powdered temporary plugging agent; if microseismic monitoring shows the fracture extension is normal, the inter-well crosstalk control is effective; if the fracture length continues to extend abnormally, the inter-well crosstalk control is ineffective.

[0035] Application Example 2: Inter-well crosstalk control Well B, stages 14-21, employed a combination of real-time pressure monitoring and in-fracture temporary plugging techniques. The difference between Example 2 and Example 1 is that Example 1 involves crosstalk between the same well level, while Example 2 involves crosstalk between wells. In Example 2, downhole microseismic monitoring exceeds the effective monitoring range, and a combination of real-time pressure monitoring and temporary plugging technology within the fracture is adopted.

[0036] Step 1: Through real-time monitoring of adjacent well pressure, B well is undergoing stage 14-21 fracturing. The pressure in the adjacent well C well is abnormal, rising by 22 MPa. Artificial fractures are used to connect well C well.

[0037] Step 2: Stop the pump and calculate the amount of temporary plugging agent to be added based on the simulation results, see Table 2. Figure 3 : m = 2 × H × L × W × ρ m: dosage of temporary plugging agent (kg) H: Monitoring crack height (m) L: (Here, the value is 0.15), m W: Crack width (valued at 0.011 here, obtained through simulation) ρ: Density of temporary plugging agent (kg / m³) 3 m = 2 × 44 × 0.15 × 0.011 × 1.3 × 10 3 =188.76kg.

[0038] Step 3: For Well B, perform fracturing stages 14-21, adding 200 kg of 1mm to 3mm powder temporary plugging agent. Real-time pressure monitoring showed that after stage 21, the pressure in adjacent wells stabilized, indicating effective control of inter-well crosstalk. (See attached image) Figure 4 .

[0039] Application Example 3: Inter-well crosstalk control Employing a combination of real-time pressure monitoring, real-time downhole microseismic monitoring, and in-fracture temporary plugging technology. The difference between Example 3 and Example 2 is that Example 2 uses a combination of real-time pressure monitoring and in-fracture temporary plugging technology, while Example 3 uses a combination of real-time pressure monitoring, downhole microseismic real-time monitoring, and in-fracture temporary plugging technology.

[0040] Step 1: Real-time monitoring of pressure in adjacent wells. Well D is fractured, and the pressure in adjacent well E is abnormal. Real-time monitoring of microseismic activity shows that the fracture propagation in well D is abnormal, and the distant fracture connects to adjacent well E.

[0041] Step 2: Stop the pump and calculate the amount of temporary plugging agent to be added based on the real-time microseismic monitoring results: m = 2 × H × L × W × ρ m: dosage of temporary plugging agent (kg) H: Monitoring crack height (m) L: Temporary occlusion depth (m) W: Crack width m ρ: Density of temporary plugging agent (kg / m³)3 .

[0042] Step 3: Fracturing well D, adding m kg of 1mm to 3mm powdered temporary plugging agent, and monitoring the pressure of the adjacent well E in real time to ensure that the pressure tends to stabilize, and monitoring the microseismic activity to ensure that the fracture extension is normal, indicating that the inter-well crosstalk is effectively controlled.

[0043] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A method for real-time control of crosstalk during fracturing in well groups, characterized in that... include: During the fracturing process, downhole microseismic monitoring is used to monitor the fracture extension morphology of the fracturing well in real time, and pressure monitoring is performed on adjacent wells in real time to determine the crosstalk type of the fracturing well. The amount of temporary plugging agent to be used is determined based on the type of crosstalk in the fracturing well; Crosstalk is controlled using the determined amount of temporary plugging agent. After crosstalk mitigation, the effectiveness of the mitigation is determined by the pressure changes in adjacent wells and the fracture extension morphology.

2. The real-time control method for well group fracturing interference according to claim 1, characterized in that, Crosstalk types in fractured wells include one or more of the following: inter-well crosstalk and crosstalk between well classes.

3. The real-time control method for well group fracturing interference according to claim 2, characterized in that, When the crosstalk type of a fractured well is inter-well crosstalk, the pressure in the adjacent well increases, and the artificial fractures extend to the adjacent well.

4. The real-time control method for well group fracturing interference according to claim 3, characterized in that, When the crosstalk type of a fractured well is inter-well crosstalk, the pressure of at least one adjacent well of the fractured well will increase.

5. The real-time control method for well group fracturing interference according to claim 2, characterized in that, When the crosstalk type of a fractured well is inter-well class crosstalk, the inter-well class crosstalk level is one or more.

6. The real-time control method for well group fracturing interference according to claim 1, 2, or 3, characterized in that, When using downhole microseismic real-time monitoring of fracture extension morphology in fractured wells, the parameters of the real-time microseismic monitoring include at least the width, length, and height of the fracture.

7. The real-time control method for well group fracturing interference according to claim 4, characterized in that, When using downhole microseismic real-time monitoring of fracture extension morphology in fractured wells, the parameters of the real-time microseismic monitoring include at least the width, length, and height of the fracture.

8. The real-time control method for well group fracturing interference according to claim 5, characterized in that, When using downhole microseismic real-time monitoring of fracture extension morphology in fractured wells, the parameters of the real-time microseismic monitoring include at least the width, length, and height of the fracture.

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