A method and device for full-area monitoring and instability location positioning of carbon storage caprock

Abstract

The present invention provides a method and device for full-area monitoring and instability location of a carbon sequestration caprock, comprising: determining the location of the carbon sequestration caprock according to the carbon sequestration area, arranging multiple parallel DC electrical measurement lines around the caprock through vertical drilling; conducting an electrical test before carbon sequestration to obtain a three-dimensional apparent resistivity background value of the caprock; conducting an electrical test on the caprock every several hours after CO2 injection is completed to obtain the three-dimensional apparent resistivity distribution of the caprock immediately after sequestration is completed, and determining the stability of the caprock immediately after sequestration is completed; periodically testing each measurement line to obtain a three-dimensional apparent resistivity cloud map of the caprock; subtracting the three-dimensional apparent resistivity cloud map of the caprock from the background value to obtain a change in the three-dimensional apparent resistivity of the caprock, and determining whether the caprock is unstable and determining the instability location based on a caprock instability location identification criterion. The present invention achieves full-area instability location location of the carbon sequestration caprock.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon sequestration capping layer instability position positioning and monitoring, and in particular to a method and device for full-area monitoring and instability position positioning of a carbon sequestration capping layer. Background Art

[0002] The caprock is a protective layer located above the storage layer, isolating the fluid within it and preventing it from escaping upward. It plays a crucial role in preventing CO2 leakage after carbon storage. Existing safety monitoring methods primarily focus on the environmental effects of CO2 leakage, and most of these are localized detections. They lack the means to monitor the safety of the storage geologic structure itself, making it impossible to pinpoint the location of instability in the carbon storage caprock should a disaster occur. Summary of the Invention

[0003] The present invention provides a method and device for monitoring and locating unstable positions in the entire carbon sequestration cap layer, which is used to locate unstable positions in the entire carbon sequestration cap layer. The technical solution is as follows:

[0004] On the one hand, a method for full-area monitoring and instability location positioning of a carbon sequestration cap rock is provided, comprising:

[0005] S1. Determine the location of the carbon storage cap layer according to the carbon storage area, and arrange multiple parallel direct current electrical measurement lines around the carbon storage cap layer through vertical drilling;

[0006] S2. Before carbon sequestration, perform electrical testing to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer;

[0007] S3. After the CO2 injection is completed, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed;

[0008] S4. Regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer;

[0009] S5. Subtract the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer, and determine whether the carbon sequestration cap layer is unstable and the unstable position according to a cap layer instability position identification criterion.

[0010] Optionally, the step S1 may include determining the location of the carbon sequestration caprock according to the carbon sequestration area, and arranging a plurality of parallel DC electrical measurement lines around the carbon sequestration caprock through vertical drilling, specifically including:

[0011] determining an actual storage range of carbon sequestration according to a carbon sequestration engineering design, and determining a carbon sequestration cap rock region according to the actual storage range;

[0012] Multiple holes were drilled vertically at a distance of 5 m from the carbon storage caprock, and multiple parallel DC electrical measurement lines were arranged;

[0013] The spacing between each DC electrical measurement line hole is 20m, and the distance between multiple electrodes in the measurement line hole is 5m. To ensure that the detection area covers the entire cap layer of the storage area, the length of the DC electrical measurement line hole should be more than 3 times the length of the cap layer. If the cap layer length is l, the measurement line hole length L>3l;

[0014] The number of measuring holes is determined by the width of the cap layer. If the cap layer width is m meters, the number of measuring holes n>m / 20; each measuring hole is connected to the well electrical data acquisition system to perform DC electrical testing.

[0015] Optionally, before carbon sequestration in S2, electrical testing is performed to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer, specifically including:

[0016] Before CO2 storage, the caprock is electrically tested every other day to obtain the initial apparent resistivity value of the caprock before carbon storage. A 3D inversion is then performed to draw a 3D cloud map of the apparent resistivity until the results of the two tests remain stable.

[0017] The test results remain stable when the difference between the apparent resistivity values of two adjacent tests at all measuring points is within 5%. In this case, the last test result is taken as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration.

[0018] The result of each measuring point is ρ(x,y,z), and the 3D cloud map is a set of {ρ(x,y,z)} consisting of the apparent resistivity of each point;

[0019] Assume that the 3D cloud image result obtained by the nth test is {ρ n (x,y,z)}, if the test results of two adjacent test points at each measuring point satisfy -0.05<[ρ n (x,y,z)-ρ n-1 (x,y,z)] / ρ n-1 (x,y,z)<0.05, it means the cloud is stable. n (x, y, z)} is used as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration, denoted as {ρ b (x,y,z)}.

[0020] Optionally, after the CO2 injection is completed in S3, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain a three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed, including:

[0021] After carbon sequestration is completed, an electrical test is performed on the carbon sequestration cap layer every several hours to obtain the three-dimensional apparent resistivity distribution of the cap layer immediately after carbon sequestration is completed;

[0022] The three-dimensional apparent resistivity distribution values {ρ c (x,y,z)}, and the three-dimensional apparent resistivity background value of the cover layer before carbon sequestration {ρ b (x,y,z)} is the difference;

[0023] If -0.05<[ρ c (x,y,z)-ρ b (x,y,z)] / ρ b If (x,y,z)<0.05, it means that the caprock is in an unstable state just after carbon sequestration. When the above formula is satisfied, it indicates that the caprock has returned to stability after carbon sequestration, and regular monitoring is then carried out in the later stage.

[0024] Optionally, the step S4 of periodically testing each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer specifically includes:

[0025] After the sealing is completed and the caprock is restored to stability, periodic electrical tests are carried out on each measuring line. Each measuring line is tested continuously to avoid errors caused by interference. The time interval for each measuring line is 10 minutes and the frequency is once a day. The test data is inverted to obtain a three-dimensional apparent resistivity cloud map {ρ d (x,y,z)}.

[0026] Optionally, the step S5 of subtracting the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from a background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer specifically includes:

[0027] The apparent resistivity cloud map {ρ d (x,y,z)} and the background value {ρ b (x,y,z)}, and determine the abnormal coefficient λ dn , to determine whether the cover is unstable.

[0028] Optionally, judging whether the carbon sequestration cap layer is unstable and determining the instability position according to a cap layer instability position identification criterion in S5 specifically includes:

[0029] According to the variation anomaly coefficient λ dn Size to determine whether the cover is unstable;

[0030] If λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b(x,y,z)}≥0.5 or λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}≤-0.5, it indicates that the caprock is unstable;

[0031] Variation anomaly coefficient λ dn The measuring point position with a value greater than or equal to 0.5 or less than or equal to -0.5 is the position where the cover layer is unstable;

[0032] If -0.5<λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}<0.5, and the absolute value of the variation anomaly coefficient corresponding to each measuring point is less than 0.5, indicating that the cover layer is not unstable.

[0033] In another aspect, a device for full-area monitoring and unstable position location of a carbon sequestration cap layer is provided, comprising:

[0034] an arrangement module, configured to determine the position of the carbon sequestration cap layer according to the carbon sequestration area, and arrange a plurality of parallel direct current electrical measurement lines around the carbon sequestration cap layer through vertical drilling;

[0035] A first testing module is used to perform an electrical test before carbon sequestration to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer;

[0036] The second testing module is used to perform an electrical test on the carbon sequestration cap layer every several hours after the CO2 injection is completed, to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed;

[0037] A regular testing module, used to regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer;

[0038] The instability judgment module is used to obtain the change of the three-dimensional apparent resistivity of the carbon sequestration cap layer by subtracting the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value, and judge whether the carbon sequestration cap layer is unstable and determine the instability position according to the cap layer instability position judgment criterion.

[0039] On the other hand, an electronic device is provided, comprising a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the above-mentioned method for full-area monitoring and instability position positioning of the carbon sequestration cap layer.

[0040] On the other hand, a computer-readable storage medium is provided, wherein the storage medium stores at least one instruction, and the at least one instruction is loaded and executed by a processor to implement the above-mentioned method for full-area monitoring and instability position positioning of carbon sequestration cap layer.

[0041] Compared with the prior art, the above technical solution has at least the following beneficial effects:

[0042] This invention utilizes borehole direct current (DC) electrical method technology to provide a method for monitoring and locating instability locations across the entire carbon storage caprock. By deploying multiple parallel electrical lines and electrodes within multiple vertical boreholes, DC electrical testing is performed to obtain the three-dimensional apparent resistivity background value of the caprock before storage and a three-dimensional apparent resistivity cloud map obtained from regular daily monitoring after storage. These values are then subtracted to obtain a difference cloud map, and the locations of structural instability across the entire carbon storage caprock are determined using caprock instability location identification criteria. Overall, the large-scale application of this invention could yield significant safety and economic benefits.

[0043] The main advantages of the present invention are:

[0044] 1. The present invention utilizes borehole direct current electrical method technology to provide a method for full-area monitoring and unstable position location of carbon storage caprocks. Through multi-hole monitoring and three-dimensional inversion of the apparent resistivity of the caprock, the structural changes of the full area of the carbon storage caprock are tracked and detected. According to the caprock unstable position identification criteria, the unstable position of the deep geological carbon storage caprock (including the main fracture position and size) is accurately located. The method has the advantages of high visualization, full-area monitoring, convenience, high detection precision and accuracy.

[0045] 2. The present invention uses the drilling direct current method to detect the unstable position of the carbon sequestration cap layer multiple times. The detection process is non-destructive and non-disturbant, with strong anti-interference ability, which greatly improves the recognition accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 A flow chart of a method for full-area monitoring and instability location positioning of a carbon sequestration cap rock provided by an embodiment of the present invention;

[0048] Figure 2 A flow chart of another method for full-area monitoring and instability location positioning of a carbon sequestration cap rock provided by an embodiment of the present invention;

[0049] Figure 3A schematic diagram of a scenario of a method for full-area monitoring and instability location positioning of a carbon sequestration cap rock provided by an embodiment of the present invention;

[0050] Figure 4 This is a block diagram of a device for full-area monitoring and unstable position positioning of a carbon sequestration cap layer provided by an embodiment of the present invention;

[0051] Figure 5 It is a structural diagram of an electronic device provided by an embodiment of the present invention.

[0052] Figure 3 Description of the reference numerals

[0053] 1. Cap layer; 2. Detection area; 3. Vertical drilling; 4. DC electrical measurement line; 5. Electrode; 6. Ground DC electrical measurement monitoring room; 7. DC electrical measurement instrument. DETAILED DESCRIPTION

[0054] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] like Figure 1 As shown, an embodiment of the present invention provides a method for full-area monitoring and unstable position location of a carbon sequestration cap layer, comprising:

[0056] S1. Determine the location of the carbon storage cap layer according to the carbon storage area, and arrange multiple parallel direct current electrical measurement lines around the carbon storage cap layer through vertical drilling;

[0057] S2. Before carbon sequestration, perform electrical testing to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer;

[0058] S3. After the CO2 injection is completed, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed;

[0059] S4. Regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer;

[0060] S5. Subtract the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer, and determine whether the carbon sequestration cap layer is unstable and the unstable position according to a cap layer instability position identification criterion.

[0061] The following combination Figure 2 and Figure 3 , a method for locating coal and rock fracture areas based on narrowband electromagnetic signals provided by an embodiment of the present invention is described in detail, including:

[0062] S1. Determine the location of the carbon storage cap layer according to the carbon storage area, and arrange multiple parallel direct current electrical measurement lines around the carbon storage cap layer through vertical drilling;

[0063] Optionally, the step S1 may include determining the location of the carbon sequestration caprock according to the carbon sequestration area, and arranging a plurality of parallel DC electrical measurement lines around the carbon sequestration caprock through vertical drilling, specifically including:

[0064] Before storing CO2, the actual storage range of carbon storage is determined according to the engineering design of carbon storage, and the carbon storage cap layer 1 area is determined according to the actual storage range;

[0065] A plurality of holes 3 are vertically drilled at a position 5 m away from the carbon storage cap layer, and a plurality of parallel DC electrical measurement lines 4 are arranged in the vertical drill holes 3;

[0066] The spacing between each DC electrical measurement line hole is 20m, and the spacing between multiple electrodes 5 in the measurement line hole is 5m, thereby obtaining the DC electrical detection area 2. To ensure that the detection area 2 covers the entire cap layer 1 of the storage area, the length of the DC electrical measurement line holes should exceed 3 times the length of the cap layer. The cap layer length is l, and the measurement line hole length L>3l. A DC electrical monitoring room 6 is established on the ground and the DC electrical measurement line 4 and electrodes 5 are connected to the electrical instrument 7.

[0067] The number of survey holes is determined by the width of the cover layer. If the cover layer width is m meters, the number of survey holes n>m / 20;

[0068] Connect each measuring line hole to the well electrical data acquisition system to perform DC electrical testing.

[0069] S2. Before carbon sequestration, perform electrical testing to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer;

[0070] Optionally, before carbon sequestration in S2, electrical testing is performed to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer, specifically including:

[0071] Before CO2 storage, the caprock is electrically tested every other day to obtain the initial apparent resistivity value of the caprock before carbon storage. A 3D inversion is then performed to draw a 3D cloud map of the apparent resistivity until the results of the two tests remain stable.

[0072] The test results remain stable when the difference between the apparent resistivity values of two adjacent tests at all measuring points is within 5%. In this case, the last test result is taken as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration.

[0073] The result of each measuring point is ρ(x,y,z), and the 3D cloud map is a set of {ρ(x,y,z)} consisting of the apparent resistivity of each point;

[0074] Assume that the 3D cloud image result obtained by the nth test is {ρ n (x,y,z)}, if the test results of two adjacent test points at each measuring point satisfy -0.05<[ρ n (x,y,z)-ρ n-1 (x,y,z)] / ρ n-1 (x,y,z)<0.05, it means the cloud is stable. n (x, y, z)} is used as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration, denoted as {ρ b (x,y,z)}.

[0075] S3. After the CO2 injection is completed, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed;

[0076] Optionally, after the CO2 injection is completed in S3, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain a three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed, including:

[0077] After carbon sequestration is completed, an electrical test is performed on the carbon sequestration cap layer every several hours (for example, 3 hours) to obtain the three-dimensional apparent resistivity distribution of the cap layer immediately after carbon sequestration is completed;

[0078] The three-dimensional apparent resistivity distribution values {ρ c (x,y,z)}, and the three-dimensional apparent resistivity background value of the cover layer before carbon sequestration {ρ b (x,y,z)} is the difference;

[0079] If -0.05<[ρ c (x,y,z)-ρ b (x,y,z)] / ρ b If (x,y,z)<0.05, it means that the caprock is in an unstable state just after carbon sequestration. When the above formula is satisfied, it indicates that the caprock has returned to stability after carbon sequestration, and regular monitoring is then carried out in the later stage.

[0080] S4. Regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer;

[0081] Optionally, the step S4 of periodically testing each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer specifically includes:

[0082] After the sealing is completed and the caprock is restored to stability, periodic electrical tests are carried out on each measuring line. Each measuring line is tested continuously to avoid errors caused by interference. The time interval for each measuring line is 10 minutes and the frequency is once a day. The test data is inverted to obtain a three-dimensional apparent resistivity cloud map {ρ d (x,y,z)}.

[0083] S5. Subtract the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer, and determine whether the carbon sequestration cap layer is unstable and the unstable position according to a cap layer instability position identification criterion.

[0084] Optionally, the step S5 of subtracting the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from a background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer specifically includes:

[0085] The apparent resistivity cloud map {ρ d (x,y,z)} and the background value {ρ b (x,y,z)}, and determine the abnormal coefficient λ dn , to determine whether the cover is unstable.

[0086] Optionally, judging whether the carbon sequestration cap layer is unstable and determining the instability position according to a cap layer instability position identification criterion in S5 specifically includes:

[0087] According to the variation anomaly coefficient λ dn Size to determine whether the cover is unstable;

[0088] If λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}≥0.5 or λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}≤-0.5, it indicates that the caprock is unstable;

[0089] Variation anomaly coefficient λ dnThe measuring point position greater than or equal to 0.5 or less than or equal to -0.5 is the position where the cover layer is unstable; measures can be taken to plug the leak and repair it to restore the stability of the cover layer.

[0090] If -0.5<λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}<0.5, and the absolute value of the variation anomaly coefficient corresponding to each measuring point is less than 0.5, indicating that the cover layer is not unstable.

[0091] Steps S4 and S5 may be repeated to continue regular monitoring.

[0092] All specific values in the embodiments of the present invention, such as a position 5 m from the carbon sequestration cap, a spacing of 20 m between each DC electrical measurement hole, a spacing of 5 m between multiple electrodes in the measurement hole, and a frequency of once a day, are optional and preferred examples, but the embodiments of the present invention are not limited to these values and are all within the protection scope of the embodiments of the present invention.

[0093] like Figure 4 As shown, an embodiment of the present invention further provides a device for full-area monitoring and unstable position positioning of a carbon sequestration cap layer, comprising:

[0094] Arrangement module 410, for determining the location of the carbon sequestration cap layer according to the carbon sequestration area, and arranging a plurality of parallel direct current electrical measurement lines around the carbon sequestration cap layer through vertical drilling;

[0095] A first testing module 420 is configured to perform an electrical test before carbon sequestration to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer;

[0096] The second testing module 430 is configured to perform an electrical test on the carbon sequestration cap layer every several hours after the CO2 injection is completed, to obtain a three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed;

[0097] A periodic testing module 440 is used to periodically test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer;

[0098] The instability judgment module 450 is configured to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer by subtracting the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value, and to judge whether the carbon sequestration cap layer is unstable and determine the instability location based on a cap layer instability location judgment criterion.

[0099] An embodiment of the present invention provides a device for full-area monitoring and unstable position positioning of a carbon sequestration cap layer, and its functional structure corresponds to a method for full-area monitoring and unstable position positioning of a carbon sequestration cap layer provided by an embodiment of the present invention, which will not be described in detail here.

[0100] Figure 5 It is a structural diagram of an electronic device 500 provided in an embodiment of the present invention. The electronic device 500 may have relatively large differences due to different configurations or performances, and may include one or more processors (central processing units, CPU) 501 and one or more memories 502, wherein the memory 502 stores at least one instruction, and the at least one instruction is loaded and executed by the processor 501 to implement the steps of the above-mentioned method for full-area monitoring and instability position positioning of carbon sequestration cap.

[0101] In an exemplary embodiment, a computer-readable storage medium is also provided, such as a memory device containing instructions. The instructions are executable by a processor in a terminal to implement the above-described method for monitoring the entire carbon sequestration cap layer and locating the instability position. For example, the computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, or optical data storage device.

[0102] Those skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware, or by a program to instruct the relevant hardware, and the program may be stored in a computer-readable storage medium, which may be a read-only memory, a disk, or an optical disk, etc.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for full-area monitoring and instability location of a carbon sequestration cap layer, characterized in that: include: S1. Determine the location of the carbon storage cap layer according to the carbon storage area, and arrange multiple parallel direct current electrical measurement lines around the carbon storage cap layer through vertical drilling; S2. Before carbon sequestration, perform electrical testing to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer; S3. After the CO2 injection is completed, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed; S4. Regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer; S5. Subtracting the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer, and judging whether the carbon sequestration cap layer is unstable and determining the unstable location according to a cap layer instability position identification criterion; In S1, the position of the carbon sequestration cap rock is determined according to the carbon sequestration area, and a plurality of parallel DC electrical measurement lines are arranged around the carbon sequestration cap rock through vertical drilling, specifically including: determining an actual storage range of carbon sequestration according to a carbon sequestration engineering design, and determining a carbon sequestration cap rock region according to the actual storage range; Drill multiple holes vertically at a distance of 5 m from the carbon storage caprock, and arrange multiple parallel DC electrical measurement lines in the vertical boreholes; The spacing between each DC electrical measurement line hole is 20m, and the distance between multiple electrodes in the measurement line hole is 5m. To ensure that the detection area covers the entire cap layer of the storage area, the length of the DC electrical measurement line hole should be more than 3 times the length of the cap layer. If the cap layer length is l, the measurement line hole length L>3l; The number of measuring holes is determined by the width of the caprock. If the caprock width is m meters, the number of measuring holes n>m / 20. Each measuring hole is connected to the wellbore electrical data acquisition system to perform DC electrical testing. Before carbon sequestration in S2, electrical testing is performed to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer, specifically including: Before CO2 storage, the caprock is electrically tested every other day to obtain the initial apparent resistivity value of the caprock before carbon storage. A 3D inversion is then performed to draw a 3D cloud map of the apparent resistivity until the results of the two tests remain stable. The test results remain stable when the difference between the apparent resistivity values of two adjacent tests at all measuring points is within 5%. In this case, the last test result is taken as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration. The result of each measuring point is ρ(x,y,z), and the 3D cloud map is a set of {ρ(x,y,z)} consisting of the apparent resistivity of each point; Assume that the 3D cloud image result obtained by the nth test is {ρ n (x,y,z)}, if the test results of two adjacent test points at each measuring point satisfy -0.05<[ρ n (x,y,z)-ρ n-1 (x,y,z)] / ρ n-1 (x,y,z)<0.05, it means the cloud is stable. n (x, y, z)} is used as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration, denoted as {ρ b (x,y,z)}; After the CO2 injection is completed in S3, the carbon sequestration cap layer is subjected to an electrical test every several hours to obtain the three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed, including: After carbon sequestration is completed, an electrical test is performed on the carbon sequestration cap layer every several hours to obtain the three-dimensional apparent resistivity distribution of the cap layer immediately after carbon sequestration is completed; The three-dimensional apparent resistivity distribution values {ρ c (x,y,z)}, and the three-dimensional apparent resistivity background value of the cover layer before carbon sequestration {ρ b (x,y,z)} is the difference; If -0.05<[ρ c (x,y,z)-ρ b (x,y,z)] / ρ b If (x,y,z)<0.05, it means that the caprock is in an unstable state just after carbon sequestration. When the above formula is satisfied, it indicates that the caprock has returned to stability after carbon sequestration, and regular monitoring is then carried out in the later stage.

2. The method according to claim 1, characterized in that In S4, each measuring line is tested regularly to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer, specifically including: After the sealing is completed and the caprock is restored to stability, periodic electrical tests are carried out on each measuring line. Each measuring line is tested continuously to avoid errors caused by interference. The time interval for each measuring line is 10 minutes and the frequency is once a day. The test data is inverted to obtain a three-dimensional apparent resistivity cloud map {ρ d (x,y,z)}.

3. The method according to claim 2, characterized in that The step S5 subtracts the three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from the background value to obtain the three-dimensional apparent resistivity change of the carbon sequestration cap layer, specifically including: The apparent resistivity cloud map {ρ d (x,y,z)} and the background value {ρ b (x,y,z)}, and determine the abnormal coefficient λ dn , to determine whether the cover is unstable.

4. The method according to claim 3, characterized in that In S5, judging whether the carbon sequestration cap layer is unstable and determining the instability position according to the cap layer instability position identification criterion specifically includes: According to the variation anomaly coefficient λ dn Size to determine whether the cover is unstable; If λ dn = [{ρ d (x,y,z)} - {ρ b (x,y,z)}] / {ρ b (x,y,z)} ≥ 0.5 or λ dn = [{ρ d (x,y,z)} - {ρ b (x,y,z)}] / {ρ b (x,y,z)} ≤ -0.5, it indicates that the caprock is unstable; Variation anomaly coefficient λ dn The measuring point position with a value greater than or equal to 0.5 or less than or equal to -0.5 is the position where the cover layer is unstable; If -0.5<λ dn =[{ρ d (x,y,z)}-{ρ b (x,y,z)}] / {ρ b (x,y,z)}<0.5, and the absolute value of the variation anomaly coefficient corresponding to each measuring point is less than 0.5, indicating that the cover layer is not unstable.

5. A device for full-area monitoring and unstable position positioning of carbon storage cap layer, characterized in that: include: an arrangement module, configured to determine the position of the carbon sequestration cap layer according to the carbon sequestration area, and arrange a plurality of parallel direct current electrical measurement lines around the carbon sequestration cap layer through vertical drilling; A first testing module is used to perform an electrical test before carbon sequestration to obtain a three-dimensional apparent resistivity background value of the carbon sequestration cap layer; The second testing module is configured to perform an electrical test on the carbon sequestration cap layer every several hours after the CO2 injection is completed, to obtain a three-dimensional apparent resistivity distribution of the carbon sequestration cap layer immediately after the sealing is completed, and to determine the stability of the carbon sequestration cap layer immediately after the sealing is completed; A regular testing module, used to regularly test each measuring line to obtain a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer; an instability judgment module, configured to obtain a change in the three-dimensional apparent resistivity of the carbon sequestration cap layer by subtracting a three-dimensional apparent resistivity cloud map of the carbon sequestration cap layer from a background value, and to judge whether the carbon sequestration cap layer is unstable and determine the instability location based on a cap layer instability location judgment criterion; The arrangement module is specifically used to: determining an actual storage range of carbon sequestration according to a carbon sequestration engineering design, and determining a carbon sequestration cap rock region according to the actual storage range; Drill multiple holes vertically at a distance of 5 m from the carbon storage caprock, and arrange multiple parallel DC electrical measurement lines in the vertical boreholes; The spacing between each DC electrical measurement line hole is 20m, and the distance between multiple electrodes in the measurement line hole is 5m. To ensure that the detection area covers the entire cap layer of the storage area, the length of the DC electrical measurement line hole should be more than 3 times the length of the cap layer. If the cap layer length is l, the measurement line hole length L>3l; The number of measuring holes is determined by the width of the caprock. If the caprock width is m meters, the number of measuring holes n>m / 20. Each measuring hole is connected to the wellbore electrical data acquisition system to perform DC electrical testing. The first test module is specifically used to: Before CO2 storage, the caprock is electrically tested every other day to obtain the initial apparent resistivity value of the caprock before carbon storage. A 3D inversion is then performed to draw a 3D cloud map of the apparent resistivity until the results of the two tests remain stable. The test results remain stable when the difference between the apparent resistivity values of two adjacent tests at all measuring points is within 5%. In this case, the last test result is taken as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration. The result of each measuring point is ρ(x,y,z), and the 3D cloud map is a set of {ρ(x,y,z)} consisting of the apparent resistivity of each point; Assume that the 3D cloud image result obtained by the nth test is {ρ n (x,y,z)}, if the test results of two adjacent test points at each measuring point satisfy -0.05<[ρ n (x,y,z)-ρ n-1 (x,y,z)] / ρ n-1 (x,y,z)<0.05, it means the cloud is stable. n (x, y, z)} is used as the three-dimensional apparent resistivity background value of the cap layer before carbon sequestration, denoted as {ρ b (x,y,z)}; The second test module is specifically used to: After carbon sequestration is completed, an electrical test is performed on the carbon sequestration cap layer every several hours to obtain the three-dimensional apparent resistivity distribution of the cap layer immediately after carbon sequestration is completed; The three-dimensional apparent resistivity distribution values {ρ c (x,y,z)}, and the three-dimensional apparent resistivity background value of the cover layer before carbon sequestration {ρ b (x,y,z)} is the difference; If -0.05<[ρ c (x,y,z)-ρ b (x,y,z)] / ρ b If (x,y,z)<0.05, it means that the caprock is in an unstable state just after carbon sequestration. When the above formula is satisfied, it indicates that the caprock has returned to stability after carbon sequestration, and regular monitoring is then carried out in the later stage.

6. An electronic device comprising a processor and a memory, wherein the memory stores at least one instruction, characterized in that: The at least one instruction is loaded and executed by the processor to implement the method for full-area monitoring and instability position positioning of a carbon sequestration cap layer as claimed in any one of claims 1 to 4.

7. A computer-readable storage medium, wherein at least one instruction is stored in the storage medium, characterized in that: The at least one instruction is loaded and executed by the processor to implement the method for full-area monitoring and instability position positioning of a carbon sequestration cap layer as claimed in any one of claims 1 to 4.

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