Crack transformation parameter optimization method based on wide-area electromagnetic method and temperature logging method

Abstract

The invention discloses a fracture reformation parameter optimization method based on a wide-area electromagnetic method and a temperature logging method, and the method specifically comprises the steps: designing fracturing reformation parameters and a pumping program according to the characteristics of a reservoir and reformation target parameters; carrying out first temperature logging; carrying out wide-area electromagnetic method crack monitoring preparation work, and arranging a detection device on the ground around a monitoring well; fracturing construction is carried out, in the construction process, a wide-area electromagnetic method is carried out to monitor the crack, and the crack length, the crack width and the crack swept area of the crack are obtained; second-time temperature logging is conducted within 1-4 h after fracturing construction is finished, and a fracture height parameter is obtained in combination with the first temperature curve; and comparing the obtained parameters of the crack length, the crack width and the crack height with reconstruction target parameters, evaluating the crack reconstruction degree, and repeating the steps until a reconstruction target is achieved. According to the method, the problem that hydraulic fractures cannot be effectively monitored and evaluated due to the fact that the well distance between the target well and the monitoring adjacent well is too large in the prior art is solved.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic fracturing technology for oil and gas development, specifically involving a method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method. Background Technology

[0002] Currently, the most commonly used technique for monitoring hydraulic fractures is downhole microseismic monitoring. However, this requires a relatively small distance between the target well and the adjacent monitoring well, typically 500–800 meters. As the distance between the target well and the adjacent monitoring well increases, the monitoring signal weakens, and the monitoring data becomes highly inaccurate. This is especially true in the oil and gas exploration field, where the distance between exploration wells is generally greater than two kilometers, making it impossible to meet the distance requirements for downhole microseismic monitoring of adjacent wells. Summary of the Invention

[0003] The purpose of this invention is to provide a method for optimizing fracture modification parameters based on wide-area electromagnetic method and temperature logging method, which solves the problem in the prior art that hydraulic fractures cannot be effectively monitored and evaluated due to the large well distance between the target well and the monitoring well.

[0004] The technical solution adopted in this invention is a method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method, which specifically includes the following steps: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; S2: Conduct the first temperature logging and obtain the first temperature curve; S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter. S6: Compare the fracture length, fracture width, and fracture height parameters with the corresponding parameters of the modification target to evaluate whether the degree of fracture modification has reached the design target: if the degree of modification has reached the design target, then proceed with the modification according to the design plan; otherwise, optimize and adjust the modification parameters and pumping program based on the fracturing monitoring results. S7: Repeat S4~S6 until the crack modification reaches the design target.

[0005] The invention is further characterized by: In S1, the fracturing stimulation parameters and pumping procedures are designed as follows: Based on the reservoir's fracturing geological characteristics, including permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation target parameters and fracture parameters, the fracturing fluid and proppant are selected, and the fracturing stimulation parameters, including displacement, sand volume, sand ratio, and pre-flush fluid ratio, are designed, and the construction pumping procedure is optimized; the stimulation target parameters include fracture length, fracture width, and fracture height.

[0006] The specific operations for the first temperature logging in S2 and the second temperature logging in S5 are as follows: a cable carrying a well temperature instrument is lowered into the wellbore to collect temperature data at different well depths, forming a continuous temperature logging curve.

[0007] In S3, detection devices are deployed on the ground around the monitoring well, including the deployment of measuring points on the surface. For vertical wells, 2 to 3 rings of wide-area electromagnetic fracture monitoring measuring points are arranged along the circumference of the vertical well shaft. The straight-line distance between adjacent measuring points in the same ring is 10m, and the distance between two adjacent rings is 11m.

[0008] In S3, detection devices are deployed on the ground around the monitoring well, including the deployment of measuring points on the ground surface. Horizontal well wide-area electromagnetic fracture monitoring measuring points are evenly arranged on both sides of the horizontal section of the horizontal well shaft, forming two horizontal measuring lines. The length of the measuring lines covers the range of the horizontal section, and the straight-line distance between adjacent measuring points is 10m.

[0009] The specific operation of wide-area electromagnetic monitoring in S4 is as follows: AC power is supplied into the wellbore, and the wellbore and fracturing fluid form an integrated underground conductor. The underground conductor generates an antenna effect. By deploying measuring points on the surface, the signal distribution of the antenna effect is measured, the abnormal response caused by fracturing is extracted, and the sweep range of the fracturing fluid is calculated. Thus, the length, width, and area of ​​the fracture can be determined.

[0010] The fracture height parameter is obtained in S5 by comparing the first temperature curve with the second temperature curve obtained from the second temperature logging. The position where the temperature in the second temperature curve deviates from the first temperature curve is the fracture height expansion position, and the difference between the top boundary well depth and the bottom boundary well depth is the fracture height parameter.

[0011] S6 evaluates whether the fracture stimulation degree has achieved the design target and optimizes and adjusts the stimulation parameters and pumping program based on the fracturing monitoring results. Specifically, it compares the fracture length, fracture width, and fracture height obtained from wide-area electromagnetic fracture monitoring and temperature logging with the fracture length, fracture width, and fracture height parameters designed for reservoir stimulation. If the crack length and width obtained by wide-area electromagnetic crack monitoring are not lower than the crack length and width designed for the modification target, then the pre-filled liquid ratio and sand quantity parameters remain unchanged. If the crack length and width obtained by wide-area electromagnetic crack monitoring are lower than the crack length and width designed for the modification target, then increase the proportion of pre-filled liquid and the amount of sand. If the fracture height obtained from temperature logging is greater than the designed fracture height for the target modification, the discharge rate needs to be reduced to control the fracture height expansion. If the fracture height obtained from temperature logging is not greater than the fracture height designed for the target of the modification, and the fracture height well depth range is not less than the longitudinal height of the reservoir to be modified, then the original discharge rate will remain unchanged. If the fracture height obtained from temperature logging is not greater than the designed fracture height for the target reservoir, and the fracture height well depth range is less than the longitudinal height of the reservoir to be modified, then the discharge rate needs to be increased.

[0012] The beneficial effects of this invention are: This invention presents a fracture stimulation parameter optimization method based on wide-area electromagnetic logging and temperature logging, overcoming the limitations of downhole microseismic monitoring methods regarding well spacing and adjacent wells. It can accurately and efficiently identify fracture length, bandwidth, and height. The combined use of these two monitoring methods allows for a more reasonable evaluation of reservoir stimulation levels. By monitoring and evaluating fracture propagation, fracturing parameters and scheme design can be optimized and adjusted more specifically and rationally, improving reservoir stimulation effectiveness and reducing operational risks. Attached Figure Description

[0013] Figure 1 This is a flowchart of the fracture stimulation parameter optimization method based on wide-area electromagnetic method and temperature logging method of the present invention; Figure 2 This is a temperature distribution curve given by temperature logging in the fracture stimulation parameter optimization method based on wide-area electromagnetic method and temperature logging method of this invention; Figure 3 This is a schematic diagram of the layout of vertical well monitoring points for fracture detection using the wide-area electromagnetic method in the fracture stimulation parameter optimization method based on the wide-area electromagnetic method and temperature logging method of this invention. Figure 4 This is a schematic diagram of the layout of horizontal well monitoring points for fracture stimulation using the wide-area electromagnetic method in the fracture stimulation parameter optimization method based on the wide-area electromagnetic method and temperature logging method of this invention.

[0014] In the figure, 1. Vertical wellbore; 2. Vertical well wide-area electromagnetic method fracture monitoring point; 3. Horizontal wellbore; 4. Horizontal well wide-area electromagnetic method fracture monitoring point; 5. Second temperature curve; 6. First temperature curve. Detailed Implementation

[0015] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0016] This invention relates to a method for optimizing fracture stimulation parameters based on wide-area electromagnetic methods and temperature logging methods, such as... Figure 1 As shown, the specific steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters.

[0017] The design of fracturing stimulation parameters and pumping procedures involves: based on the reservoir's fracturing geological characteristics, including permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation target parameters and fracture parameters, selecting fracturing fluid and proppant, and designing fracturing stimulation parameters including displacement, sand volume, sand ratio, and pre-fracturing fluid ratio, and optimizing the construction pumping procedure; the stimulation target parameters include fracture length, fracture width, and fracture height.

[0018] S2: Conduct the first temperature logging and obtain the first temperature curve.

[0019] After completing wellbore preparations such as well washing and pressure testing, temperature logging is conducted to obtain temperature curves that vary with the length of the well section. Temperature logging primarily evaluates fracture height by comparing well temperatures before and after fracturing. When using temperature logging, it is only necessary to perform temperature logging before and after fracturing. In specific operations, a well temperature instrument is lowered into the wellbore via a cable to collect temperature data at different depths, forming continuous temperature logging curves. The first temperature curve is shown in Figure 6. Figure 2 As shown.

[0020] S3: Conduct preparatory work for wide-area electromagnetic crack monitoring, and deploy detection devices on the ground around the monitoring well.

[0021] Detection devices are deployed on the ground around the monitoring well, including measuring points on the surface. For the vertical well, 2-3 concentric rings of wide-area electromagnetic fracture monitoring measuring points are arranged along the circumference of the wellbore. The straight-line distance between adjacent measuring points within the same ring is 10m, and the distance between two adjacent rings is 11m. Figure 3 As shown.

[0022] This also includes deploying measuring points on the surface. Horizontal well wide-area electromagnetic fracture monitoring measuring points 4 are evenly arranged on both sides of the horizontal section of the horizontal wellbore 3, forming two horizontal measuring lines. The length of the measuring lines covers the horizontal section, and the straight-line distance between adjacent measuring points is 10m. Figure 4 As shown.

[0023] S4: Conduct hydraulic fracturing operations. During the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area.

[0024] Wide-area electromagnetic method is an artificial source frequency domain electromagnetic sounding method. It is simple to use. It only requires setting up sampling points around the well section, establishing a harmonic electromagnetic field with an artificial grounded field source, and sending alternating currents of different frequencies into the ground. In a large area that is not limited to the traditional "far area", one or more electromagnetic field components are observed, and the wide-area apparent resistivity is calculated to achieve the purpose of detecting geological targets at different burial depths.

[0025] Wide-area electromagnetic monitoring involves supplying alternating current into the wellbore, where the wellbore and fracturing fluid form an integrated underground conductor. This underground conductor generates an antenna effect. By deploying measuring points on the surface and measuring the signal distribution of the antenna effect, the abnormal response caused by fracturing can be extracted, and the spread range of the fracturing fluid can be calculated. This allows the determination of the fracture length, width, and area affected by the fracture.

[0026] S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter.

[0027] like Figure 2 As shown, the second temperature curve 5 is obtained through the second temperature logging. The second temperature curve 5 after fracturing is compared with the first temperature curve 6 before fracturing. The position where the temperature in the second temperature curve 5 deviates from the first temperature curve 6 is the position of fracture height expansion. The difference between the top boundary well depth and the bottom boundary well depth is the fracture height parameter.

[0028] S6: Compare the obtained fracture length, width, and height parameters with the target parameters to evaluate whether the degree of fracture modification has reached the design target; if the degree of modification has reached the design target, then proceed with the modification according to the design plan; otherwise, optimize and adjust the modification parameters and pumping program based on the fracturing monitoring results. Specifically, the fracture length, width, and height obtained from wide-area electromagnetic fracture monitoring, as well as the fracture height obtained from temperature logging, are compared with the fracture length, width, and height parameters designed for reservoir stimulation. If the crack length and width obtained by wide-area electromagnetic crack monitoring are not lower than the crack length and width designed for the modification target, then the original modification target parameters shall be maintained. If the crack length and width obtained by wide-area electromagnetic crack monitoring are lower than the crack length and width designed for the modification target, then increase the proportion of pre-filled liquid and the amount of sand. If the fracture height obtained from temperature logging is greater than the designed fracture height for the target modification, the discharge rate needs to be reduced to control the fracture height expansion. If the fracture height obtained from temperature logging is not greater than the fracture height designed for the target of the modification, and the fracture height well depth range is not less than the longitudinal height of the reservoir to be modified, then the original discharge rate will remain unchanged. If the fracture height obtained from temperature logging is not greater than the designed fracture height for the target reservoir, and the fracture height well depth range is less than the longitudinal height of the reservoir to be modified, then the discharge rate needs to be increased.

[0029] S7: Repeat S4~S6 until the crack modification reaches the design target.

[0030] Multi-stage wells can be monitored and evaluated according to S1~S7 above. The degree of modification can be evaluated based on the monitoring results. Based on the evaluation, the modification parameters and construction pumping procedures can be further optimized and adjusted to improve the reliability of the scheme implementation and increase the volume of fracture modification.

[0031] Example 1 This embodiment provides a method for optimizing fracture stimulation parameters based on wide-area electromagnetic methods and temperature logging methods, such as... Figure 1 As shown, the specific steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; S2: Conduct the first temperature logging and obtain the first temperature curve; S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter. S6: Compare the fracture length, fracture width, and fracture height parameters with the corresponding parameters of the modification target to evaluate whether the degree of fracture modification has reached the design target: if the degree of modification has reached the design target, then proceed with the modification according to the design plan; otherwise, optimize and adjust the modification parameters and pumping program based on the fracturing monitoring results. S7: Repeat S4~S6 until the crack modification reaches the design target.

[0032] Example 2 This embodiment provides a method for optimizing fracture stimulation parameters based on wide-area electromagnetic methods and temperature logging methods, such as... Figure 1 As shown, the specific steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; The design of fracturing stimulation parameters and pumping procedures involves: based on the reservoir's fracturing geological characteristics, including permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation target parameters and fracture parameters, selecting fracturing fluid and proppant, and designing fracturing stimulation parameters including displacement, sand volume, sand ratio, and pre-fracturing fluid ratio, and optimizing the construction pumping procedure; the stimulation target parameters include fracture length, fracture width, and fracture height.

[0033] S2: Conduct the first temperature logging and obtain the first temperature curve; Temperature logging involves using a cable-driven well temperature instrument to collect temperature data at different depths within the wellbore, thus creating a continuous temperature logging curve.

[0034] S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; This includes deploying measuring points on the surface, and arranging 2-3 rings of wide-area electromagnetic fracture monitoring measuring points along the circumference of the vertical wellbore. The straight-line distance between adjacent measuring points in the same ring is 10m, and the distance between two adjacent rings is 11m.

[0035] S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. Wide-area electromagnetic monitoring involves supplying alternating current into the wellbore, where the wellbore and fracturing fluid form an integrated underground conductor. This underground conductor generates an antenna effect. By deploying measuring points on the surface and measuring the signal distribution of the antenna effect, the abnormal response caused by fracturing can be extracted, and the spread range of the fracturing fluid can be calculated. This allows the determination of the fracture length, width, and area affected by the fracture.

[0036] S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter. To obtain the fracture height parameter, specifically, the first temperature curve is compared with the second temperature curve obtained from the second temperature logging. The position where the temperature in the second temperature curve deviates from the first temperature curve is the fracture height expansion position, and the difference between the top boundary well depth and the bottom boundary well depth is the fracture height parameter.

[0037] S6: Compare the fracture length, fracture width, and fracture height parameters with the corresponding parameters of the modification target to evaluate whether the degree of fracture modification has reached the design target: if the degree of modification has reached the design target, then proceed with the modification according to the design plan; otherwise, optimize and adjust the modification parameters and pumping program based on the fracturing monitoring results. S6 evaluates whether the fracture stimulation degree has achieved the design target and optimizes and adjusts the stimulation parameters and pumping program based on the fracturing monitoring results. Specifically, it compares the fracture length, fracture width, and fracture height obtained from wide-area electromagnetic fracture monitoring and temperature logging with the fracture length, fracture width, and fracture height parameters designed for reservoir stimulation. If the crack length and width obtained by wide-area electromagnetic crack monitoring are not lower than the crack length and width designed for the modification target, then the original modification target parameters shall be maintained. If the crack length and width obtained by wide-area electromagnetic crack monitoring are lower than the crack length and width designed for the modification target, then increase the proportion of pre-filled liquid and the amount of sand. If the fracture height obtained from temperature logging is greater than the designed fracture height for the target modification, the discharge rate needs to be reduced to control the fracture height expansion. If the fracture height obtained from temperature logging is not greater than the fracture height designed for the target of the modification, and the fracture height well depth range is not less than the longitudinal height of the reservoir to be modified, then the original discharge rate will remain unchanged. If the fracture height obtained from temperature logging is not greater than the designed fracture height for the target reservoir, and the fracture height well depth range is less than the longitudinal height of the reservoir to be modified, then the discharge rate needs to be increased.

[0038] S7: Repeat S4~S6 until the crack modification reaches the design target.

[0039] Example 3 This embodiment provides a method for optimizing fracture stimulation parameters based on wide-area electromagnetic methods and temperature logging methods, such as... Figure 1 As shown, the specific steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; The design of fracturing stimulation parameters and pumping procedures involves: based on the reservoir's fracturing geological characteristics, including permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation target parameters and fracture parameters, selecting fracturing fluid and proppant, and designing fracturing stimulation parameters including displacement, sand volume, sand ratio, and pre-fracturing fluid ratio, and optimizing the construction pumping procedure; the stimulation target parameters include fracture length, fracture width, and fracture height.

[0040] S2: Conduct the first temperature logging and obtain the first temperature curve; Temperature logging involves using a cable-driven well temperature instrument to collect temperature data at different depths within the wellbore, thus creating a continuous temperature logging curve.

[0041] S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; This includes deploying measuring points on the surface, and arranging uniformly distributed horizontal well wide-area electromagnetic fracture monitoring measuring points on both sides of the horizontal section of the horizontal well, forming two horizontal measuring lines. The length of the measuring lines covers the horizontal section, and the straight-line distance between adjacent measuring points is 10m.

[0042] S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. Wide-area electromagnetic monitoring involves supplying alternating current into the wellbore, where the wellbore and fracturing fluid form an integrated underground conductor. This underground conductor generates an antenna effect. By deploying measuring points on the surface and measuring the signal distribution of the antenna effect, the abnormal response caused by fracturing can be extracted, and the spread range of the fracturing fluid can be calculated. This allows the determination of the fracture length, width, and area affected by the fracture.

[0043] S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter. To obtain the fracture height parameter, specifically, the first temperature curve is compared with the second temperature curve obtained from the second temperature logging. The position where the temperature in the second temperature curve deviates from the first temperature curve is the fracture height expansion position, and the difference between the top boundary well depth and the bottom boundary well depth is the fracture height parameter.

[0044] S6: Compare the obtained fracture length, width, and height parameters with the target parameters to evaluate whether the degree of fracture modification has reached the design target; if the degree of modification has reached the design target, then proceed with the modification according to the design plan; otherwise, optimize and adjust the modification parameters and pumping program based on the fracturing monitoring results. S6 evaluates whether the fracture stimulation degree has achieved the design target and optimizes and adjusts the stimulation parameters and pumping program based on the fracturing monitoring results. Specifically, it compares the fracture length, fracture width, and fracture height obtained from wide-area electromagnetic fracture monitoring and temperature logging with the fracture length, fracture width, and fracture height parameters designed for reservoir stimulation. If the crack length and width obtained by wide-area electromagnetic crack monitoring are not lower than the crack length and width designed for the modification target, then the original modification target parameters shall be maintained. If the crack length and width obtained by wide-area electromagnetic crack monitoring are lower than the crack length and width designed for the modification target, then increase the proportion of pre-filled liquid and the amount of sand. If the fracture height obtained from temperature logging is greater than the designed fracture height for the target modification, the discharge rate needs to be reduced to control the fracture height expansion. If the fracture height obtained from temperature logging is not greater than the fracture height designed for the target of the modification, and the fracture height well depth range is not less than the longitudinal height of the reservoir to be modified, then the original discharge rate will remain unchanged. If the fracture height obtained from temperature logging is not greater than the designed fracture height for the target reservoir, and the fracture height well depth range is less than the longitudinal height of the reservoir to be modified, then the discharge rate needs to be increased.

[0045] S7: Repeat S4~S6 until the crack modification reaches the design target.

[0046] Example 4 This embodiment provides a method for optimizing fracture stimulation parameters based on wide-area electromagnetic methods and temperature logging methods, such as... Figure 1 As shown, the specific steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; Based on the fracturing geological characteristics of shale reservoirs, such as permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation objectives and fracture parameters, the fracturing fluid and proppant materials were optimized, and fracturing parameters and pumping procedures, including displacement, sand content, sand ratio, and pre-fracturing fluid ratio, were designed. A total of 4 sections and 11 clusters were designed, with a displacement of 14–16 m³ / s. 3 / min, sand volume 50~100m 3 , sand ratio 11~13%, liquid volume 950~1650m 3 ; S2: Conduct the first temperature logging and obtain the first temperature curve; After completing wellbore preparations such as wellbore washing and pressure testing, temperature logging is carried out to obtain temperature curves that vary with the length of the well section. S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; Before fracturing, preparations were made for wide-area electromagnetic crack monitoring. Two horizontal measuring lines were arranged along both sides of the horizontal section, with the length of the side lines covering the entire length of the horizontal section, totaling 220m. The distance between two adjacent measuring points was 10 meters, and a total of 44 measuring points were arranged. S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. The first stage of fracturing was carried out according to the predetermined design, with a displacement of 14m³ / h. 3 / min, sand volume 50m3, sand ratio 11%, liquid volume 950m 3 During the fracturing operation, wide-area electromagnetic crack monitoring was conducted, obtaining data on a single crack segment: a length of 154m, a width of 43m, and a swept area of ​​6230m². 3 ; S5: Three hours after the first stage of fracturing was completed, a second temperature logging was performed to obtain the second temperature curve, which is the wellbore temperature curve after fracturing. Compared with the first temperature curve, the fracture height was obtained as 34m. S6: Compare the first segment of fracture parameters obtained from fracture monitoring with the designed target parameters. The fracture length and fracture swept area are relatively low; the fracture height is close to the designed fracture height, and the fracture height depth range can cover the vertical depth of the target reservoir, while the discharge rate remains unchanged.

[0047] As can be seen from the above, the degree of modification in the first stage was lower than the design target. Based on the fracturing monitoring results, the fracturing software simulation parameters were corrected, and the parameters for the second stage modification were adjusted to a displacement of 14m³ / h based on the new fracturing simulation results. 3 / min, sand volume 80m 3 , sand ratio 12%, liquid volume 1350m 3 ; S7: Repeat steps S4 to S6 to finally achieve the design goal.

[0048] The second stage involves monitoring and evaluation according to S1 to S7. The degree of modification can be evaluated based on the monitoring results. Based on the evaluation, the modification parameters and construction pumping procedures can be further optimized and adjusted to improve the reliability of the scheme implementation and increase the volume of crack modification.

Claims

1. A method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method, characterized in that, Specifically, the steps include the following: S1: Design fracturing parameters and pumping procedures based on reservoir characteristics and target parameters; S2: Conduct the first temperature logging and obtain the first temperature curve; S3: Carry out preparatory work for wide-area electromagnetic crack monitoring and deploy detection devices on the ground around the monitoring well; S4: Conduct hydraulic fracturing operations, and during the operation, use wide-area electromagnetic methods to monitor the cracks and obtain the crack length, crack width, and crack spread area. S5: Perform a second temperature logging operation within 1-4 hours after the fracturing operation is completed to obtain a second temperature curve. Compare the second temperature curve with the first temperature curve to obtain the fracture height parameter. S6: Compare the crack length, crack width, and crack height parameters with the corresponding parameters of the renovation target to evaluate whether the degree of crack renovation has achieved the design target: If the degree of renovation has achieved the design target, then carry out the renovation according to the design plan; Otherwise, optimize and adjust the modification parameters and pumping procedures based on the fracturing monitoring results; S7: Repeat S4~S6 until the crack modification reaches the design target.

2. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 1, characterized in that, The design of fracturing stimulation parameters and pumping procedures described in S1 specifically involves: based on the reservoir's fracturing geological characteristics, including permeability, porosity, gas content, Young's modulus, and Poisson's ratio, and combined with the stimulation target parameters and fracture parameters, selecting fracturing fluid and proppant, designing fracturing stimulation parameters including displacement, sand volume, sand ratio, and pre-flush fluid ratio, and optimizing the construction pumping procedure; the stimulation target parameters include fracture length, fracture width, and fracture height.

3. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 1, characterized in that, The specific operations of the first temperature logging described in S2 and the second temperature logging described in S5 are as follows: a cable carrying a well temperature instrument is lowered into the wellbore to collect temperature data at different well depths, forming a continuous temperature logging curve.

4. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 1, characterized in that, In S3, detection devices are deployed on the ground around the monitoring well, including the deployment of measuring points on the surface. For vertical wells, 2 to 3 rings of wide-area electromagnetic fracture monitoring measuring points are arranged along the circumference of the vertical well shaft. The straight-line distance between adjacent measuring points in the same ring is 10m, and the distance between two adjacent rings is 11m.

5. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 1, characterized in that, In S3, detection devices are deployed on the ground around the monitoring well, including the deployment of measuring points on the ground surface. Horizontal well wide-area electromagnetic fracture monitoring measuring points are evenly arranged on both sides of the horizontal section of the horizontal well shaft, forming two horizontal measuring lines. The length of the measuring lines covers the range of the horizontal section, and the straight-line distance between adjacent measuring points is 10m.

6. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 1, characterized in that, The specific operation of the wide-area electromagnetic monitoring method described in S4 is as follows: AC power is supplied into the wellbore, and the wellbore and fracturing fluid form an integrated underground conductor. The underground conductor generates an antenna effect. By deploying measuring points on the surface, the signal distribution of the antenna effect is measured, the abnormal response caused by fracturing is extracted, and the sweep range of the fracturing fluid is calculated. Thus, the length, width, and area of ​​the fracture can be determined.

7. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 3, characterized in that, The method for obtaining the fracture height parameter as described in S5 is as follows: compare the first temperature curve with the second temperature curve obtained from the second temperature logging. The position where the temperature in the second temperature curve deviates from the first temperature curve is the fracture height expansion position, and the difference between the top boundary well depth and the bottom boundary well depth is the fracture height parameter.

8. The method for optimizing fracture stimulation parameters based on wide-area electromagnetic method and temperature logging method according to claim 7, characterized in that, S6 evaluates whether the fracture stimulation degree has achieved the design target and optimizes and adjusts the stimulation parameters and pumping program based on the fracturing monitoring results. Specifically, it compares the fracture length, fracture width, and fracture height obtained from wide-area electromagnetic fracture monitoring and temperature logging with the fracture length, fracture width, and fracture height parameters designed for reservoir stimulation. If the crack length and width obtained by wide-area electromagnetic crack monitoring are not lower than the crack length and width designed for the modification target, then the pre-filled liquid ratio and sand quantity parameters remain unchanged. If the crack length and width obtained by wide-area electromagnetic crack monitoring are lower than the crack length and width designed for the modification target, then increase the proportion of pre-filled liquid and the amount of sand. If the fracture height obtained from temperature logging is greater than the designed fracture height for the target modification, the discharge rate needs to be reduced to control the fracture height expansion. If the fracture height obtained from temperature logging is not greater than the fracture height designed for the target of the modification, and the fracture height well depth range is not less than the longitudinal height of the reservoir to be modified, then the original discharge rate will remain unchanged. If the fracture height obtained from temperature logging is not greater than the designed fracture height for the target reservoir, and the fracture height well depth range is less than the longitudinal height of the reservoir to be modified, then the discharge rate needs to be increased.

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