Method and system for judging constraint boundary of fault control reservoir well

Abstract

The invention relates to the technical field of fault control reservoir body boundary judgment, in particular to a method and system for judging a fault control reservoir body well constraint boundary. Comprising the following steps: S1, obtaining a threshold value of a target reservoir detection attribute based on a well-to-seismic calibration method; s2, depicting a reservoir body boundary for the target reservoir in the fracture direction; s3, on the basis of the threshold value of the target reservoir detection attribute, depicting a reservoir body boundary in the transverse direction of the vertical fracture direction of the target reservoir; s4, forming a three-dimensional data volume space visual display image; reservoir body division in the fracture direction and in the direction perpendicular to the fracture direction is carried out on a plane, the reservoir detection attribute three-dimensional space engraving range is combined, multi-angle reservoir body division and description are achieved, meanwhile, different types of reservoir detection attribute normalization threshold values are obtained through well-seismic calibration of a target stratum, and the reservoir detection attribute normalization threshold values are obtained. And the accuracy of the divided reservoir body is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of determination of the boundary of fault-controlled reservoirs, and particularly to a method and system for determining the well-constrained boundary of fault-controlled reservoirs. Background Art

[0002] Different from traditional sandstone reservoirs, fault-controlled fracture-cavity type oil and gas reservoirs are mainly controlled by strike-slip faults. The activity intensity of the fault zone controls the development degree of the reservoir. The length of some fault zones can reach about 60 km. The fault patterns mainly include tensile segments, compressive segments, translational segments, and oblique compressive segments. There are large differences in reservoir development among different fault patterns. The reservoir spaces are mainly caves, holes, and fractures formed by fault fractures. The spatial distribution of the reservoir is extremely irregular. The fine analysis of different reservoir bodies determines the efficient utilization evaluation of the entire fault zone. The determination of the reservoir body boundary affects the analysis of the utilization degree of the drilled wells within the reservoir body. Different reservoir bodies require different drilling utilizations. The well-constrained boundary determination method is the key to restricting the selection of well positions and well types and efficient utilization.

[0003] The prior art CN114460667A discloses a method and device for quantitatively identifying the boundary of ultra-deep fault-controlled karst reservoirs. The method includes: depicting the effective seismic attributes of the karst reservoir boundary to obtain an attribute fusion body; determining the depth of the well based on the characteristics of the karst reservoir boundary of the drilling data; determining the effective attribute value based on the well depth and combining with the attribute fusion body; establishing a geological model of the ultra-deep fault-controlled karst reservoir boundary by combining drilling data; carrying out seismic forward modeling based on the geological model, establishing a boundary quantitative identification template based on the forward modeling, and obtaining a quantitative identification threshold value; combining the effective attribute value with the quantitative identification threshold value to achieve intelligent quantitative identification. However, the above method does not consider the division of different reservoir bodies from multiple angles.

[0004] Therefore, there is an urgent need to provide a method and system for determining the well-constrained boundary of fault-controlled reservoirs, which can improve the accuracy of the division of the well-constrained boundary of reservoir bodies compared with the prior art. Summary of the Invention

[0005] The present invention solves the technical problems existing in the prior art, and provides a method and system for determining the well-constrained boundary of fault-controlled reservoirs.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for determining the well-constrained boundary of a fault-controlled reservoir body includes the following steps:

[0008] S1. Obtain the threshold value of the detection attribute of the target reservoir based on the well-seismic calibration method;

[0009] S2. Depict the reservoir body boundary along the fault direction of the target reservoir;

[0010] S3. Based on the threshold value of the target reservoir detection attribute obtained in step S1, laterally depict the reservoir body boundary along the vertical fracture direction of the target layer;

[0011] S4. Based on the reservoir body boundary depicted along the fracture direction and the lateral reservoir body boundary depicted along the vertical fracture direction, and combined with the spatial attribute of the target reservoir detection attribute, form a three-dimensional data volume spatial visualization display map.

[0012] Furthermore, S2 specifically includes the following steps:

[0013] S201. Extract the in-segment fracture detection attribute of the target reservoir;

[0014] S202. Conduct fracture segmentation difference analysis according to the fracture profile style and planar distribution law, and divide the corresponding fracture profiles with the same style and planar distribution law into the same reservoir body;

[0015] S203. Extract the production dynamic situation of the drilled wells in the target reservoir and the connectivity of reservoir bodies at different positions, and determine whether they are different reservoir bodies according to the dynamic response of the drilled wells;

[0016] S204. Determine the reservoir body boundary along the fracture direction through the analysis results of steps S202 and S203.

[0017] Even further, the fracture profile styles in step S202 at least include negative flower-shaped, positive flower-shaped, translational, and compression ridge.

[0018] Even further, the planar distribution laws of step S202 at least include left-lateral left-stepped tensile segment, left-lateral right-stepped compression segment, linear translational segment, and oblique weak compression segment.

[0019] Even further, the negative flower-shaped fracture profile style corresponds to the planar distribution law of the left-lateral left-stepped tensile segment, the positive flower-shaped fracture profile style corresponds to the planar distribution law of the left-lateral right-stepped compression segment, the translational fracture profile style corresponds to the planar distribution law of the translational segment, and the compression ridge fracture profile style corresponds to the planar distribution law of the oblique weak compression segment.

[0020] Even further, the specific determination method of S204 is: when the different drilled well dynamics within the reservoir body set in step S202 affect and respond to each other, it is set as the same reservoir body; when the different drilled well dynamics within the reservoir body set in step S202 do not affect and respond to each other, it is set as different reservoir bodies.

[0021] Furthermore, S1 specifically includes the following steps:

[0022] S101. Set the threshold value of the cave-like reservoir;

[0023] S102. Set the threshold value of the pore - type reservoir;

[0024] S103. Set the threshold value of the fracture - type reservoir.

[0025] Furthermore, the specific method of step S101 is: Through the analysis and comparison of the instantaneous energy attribute under different three - dimensional and processing methods, calibrate with the logging interpretation test of Class I reservoir or the spatial position of the blowout and leakage, and the calibration result is the threshold value of the cave - type reservoir.

[0026] Furthermore, the threshold value of the cave - type reservoir is: the instantaneous energy attribute value is greater than the first set value.

[0027] Furthermore, the specific method of step S102 is: Through the normalized comparative analysis of the seismic discontinuity attribute, calibrate with the logging interpretation test of Class II reservoir or the spatial position of the drilling micro - leakage, and the calibration result is the threshold value of the pore - type reservoir.

[0028] Furthermore, the threshold value of the pore - type reservoir is: the seismic discontinuity attribute value is greater than the second set value.

[0029] Furthermore, the specific method of step S103 is: Through the normalized comparative analysis of the coherence attribute, calibrate with the spatial position of the logging interpretation Class III reservoir, and the calibration result is the threshold value of the fracture - type reservoir.

[0030] Furthermore, the threshold value of the fracture - type reservoir is: the coherence attribute is greater than the third set value.

[0031] Furthermore, step S3 specifically includes the following steps:

[0032] S301. Identify the planar position of the cave - type reservoir according to the threshold value of the cave - type reservoir;

[0033] S302. Identify the planar position of the pore - type reservoir according to the threshold value of the pore - type reservoir;

[0034] S303. Identify the planar position of the fracture - type reservoir according to the threshold value of the fracture - type reservoir;

[0035] S304. Superimpose the identified planar position boundaries of the cave - type reservoir, the pore - type reservoir, and the fracture - type reservoir to form the lateral reservoir boundary of the target reservoir along the vertical fracture direction.

[0036] Further, the spatial attributes of the detection attributes in step S4 at least include spatial abscissa, ordinate, depth, and amplitude.

[0037] A system using the method for determining the well-constrained boundary of fault-controlled reservoir bodies described in any one of the above, comprising a first module, a second module, a third module, and a fourth module connected in sequence. The first module is used to execute the content in step S1, the second module is used to execute the content in step S2, the third module is used to execute the content in step S3, and the fourth module is used to execute the content in step S4.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] (1) In the present invention, the reservoir bodies are divided along the fracture direction and perpendicular to the fracture direction on the plane. After combining the fracture profile pattern with the plane distribution law in the reservoir body division along the fracture direction, the reservoir body division is analyzed. At the same time, the dynamic response of the drilled wells in the reservoir body is also combined to further identify and analyze the reservoir body division. Combining the three-dimensional spatial carving range of reservoir detection attributes, the division and description of reservoir bodies considering multiple angles are realized. At the same time, the threshold values of different types of reservoir detection attributes are obtained through well-seismic calibration of the target layer, making the accuracy of the divided reservoir bodies higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a flowchart of the method of the present invention.

[0041] Figure 2 is a schematic diagram of the calibration results of different types of reservoirs of the present invention.

[0042] Figure 3 is a schematic diagram of depicting the lateral reservoir body boundaries along the fracture direction and perpendicular to the fracture direction of the present invention.

[0043] Figure 4 Spatial visualization display diagram of the three-dimensional data volume of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] The technical solutions of the present invention will be clearly described below in conjunction with the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0045] As Figure 1 shown, the present invention provides a method for determining the well-constrained boundary of fault-controlled reservoir bodies, comprising the following steps:

[0046] S1. As Figure 2 shown, based on the well-seismic calibration method, the threshold values of the target reservoir detection attributes are obtained, including the threshold values of cave-type reservoirs, pore-type reservoirs, and fracture-type reservoirs, specifically:

[0047] S101. Set the threshold value for cavernous reservoirs, specifically: through the analysis and comparison of instantaneous energy attributes under different 3D and processing methods, calibrate using the logging interpretation test Class I reservoirs or the spatial positions of blowout and leakage, and the calibration result is the threshold value for cavernous reservoirs. The threshold value for cavernous reservoirs is: the instantaneous energy attribute value is greater than the first set value, and the first set value is preferably 87;

[0048] S102. Set the threshold value for vuggy reservoirs, specifically: through the normalized comparative analysis of seismic discontinuity attributes, calibrate using the logging interpretation test Class II reservoirs or the spatial positions of micro-leakage in drilling, and the calibration result is the threshold value for vuggy reservoirs. The threshold value for vuggy reservoirs is: the seismic discontinuity attribute value is greater than the second set value, and the second set value is preferably 0.22;

[0049] S103. Set the threshold value for fractured reservoirs, specifically: through the normalized comparative analysis of coherence attributes, calibrate using the spatial positions of logging interpretation Class III reservoirs, and the calibration result is the threshold value for fractured reservoirs. The threshold value for fractured reservoirs is: the coherence attribute is greater than the third set value, and the third set value is preferably 80.

[0050] S2. Characterize the reservoir body boundary along the fault direction for the target reservoir, specifically including the following steps:

[0051] S201. Extract the intra-segment fault detection attributes of the target reservoir;

[0052] S202. Conduct a differential analysis of fault segmentation based on the fault profile pattern and planar distribution law, and conduct a combined analysis from both the profile and planar perspectives. When the fault profile pattern corresponds to the planar distribution law, preliminarily divide the corresponding part into the same reservoir body; specifically, the fault profile patterns include negative flower-shaped, positive flower-shaped, translational, and compression ridges, and the planar distribution laws include left-step left-lateral tensile segments, left-step right-lateral compression segments, linear translational segments, and oblique weak compression segments. The negative flower-shaped and left-step left-lateral tensile segments describe the same reservoir body, the positive flower-shaped and left-step right-lateral compression segments describe the same reservoir body, the translational and linear translational segments describe the same reservoir body, and the compression ridge and oblique weak compression segments describe the same reservoir body;

[0053] S203. Extract the production dynamics of the drilled wells within the target reservoir and the connectivity of reservoir bodies at different positions. If there is a dynamic response in the drilled wells within the two reservoir bodies set in step S202, then these two reservoir bodies are the same reservoir body; if there is no dynamic response in the drilled wells within the two reservoir bodies set in step S202, then these two reservoir bodies are different reservoir bodies;

[0054] S204. Determine the reservoir body boundary along the fault direction through the analysis in steps S202 and S203.

[0055] S3. As Figure 3As shown in the figure, the lateral characterization boundary of the target reservoir along the vertical fracture direction specifically includes the following steps:

[0056] S301. According to the threshold value of the cave reservoir, identify the planar position of the cave reservoir with instantaneous energy greater than 87;

[0057] S302. According to the threshold value of the vuggy reservoir, identify the planar position of the vuggy reservoir with discontinuity attribute greater than 0.22;

[0058] S303. According to the threshold value of the fracture reservoir, identify the planar position of the fracture reservoir with coherence attribute greater than 80;

[0059] S304. Superimpose the identified planar position boundaries of the cave reservoir, the vuggy reservoir, and the fracture reservoir to form the lateral boundary of the reservoir body of the target reservoir in the vertical fracture direction.

[0060] S4. Based on the range formed by the reservoir body boundary along the fracture direction and the reservoir body boundary perpendicular to the fracture direction, and combined with the spatial attributes of the detection attributes of different reservoir types, form a three-dimensional data volume spatial visualization display map with three types of reservoir detection attributes, which can not only display the spatial morphology of the cave, vuggy, and fracture reservoirs, but also depict the boundaries of different reservoir bodies, realize the spatial carving of three-dimensional multi-attribute fusion, and obtain the spatial difference boundaries of different reservoir bodies in the target layer.

[0061] Furthermore, the spatial attributes of the detection attributes at least include spatial abscissa, ordinate, depth, and amplitude information.

[0062] Based on the calibration results of different types of reservoirs in the front, use the reservoir calibration threshold value to perform three-dimensional carving in the visualization environment, filter the non-reservoir space range through the threshold value, and obtain the spatial distribution results of different types of reservoirs. According to the carving results of different types of reservoirs, adopt a multi-body fusion method to further obtain the spatial difference boundaries of the reservoir body in the target layer.

[0063] Figure 4 Based on the fusion display of the carving results of different types of reservoirs, the difference boundaries of the reservoir body in the target layer can be depicted. It can be seen from the figure that the length of the fault-controlled reservoir body boundary in the east-west direction along the fracture direction is 6208 meters. The width difference in the north-south direction perpendicular to the fracture is relatively large. The northern boundary is relatively wide at 1394 meters, and the southern part is relatively narrow at 593 meters. The reservoir difference along the fracture direction is relatively obvious, and the deepest longitudinal depth is 1602m.

[0064] The present invention also provides a system for determining the boundary of the fractured and controlled reservoir body well, which includes a first module, a second module, a third module, and a fourth module connected in sequence. The first module is used to execute the content in step S1, the second module is used to execute the content in step S2, the third module is used to execute the content in step S3, and the fourth module is used to execute the content in step S4.

[0065] The present invention divides the reservoir body along the fracture direction and perpendicular to the fracture direction on a plane, and analyzes the division of the reservoir body by combining the fracture profile pattern and the plane distribution law in the division of the reservoir body along the fracture direction. At the same time, it also combines the dynamic response of the drilled wells in the reservoir body to further identify and analyze the division of the reservoir body, realizing the consideration of the division of the reservoir body from multiple angles. At the same time, the threshold values of different types of reservoir detection attributes are obtained through well-seismic calibration of the target layer, making the accuracy of the divided reservoir body higher.

[0066] Finally, it should be noted that the above content is only used to illustrate the technical solution of the present invention, rather than a limitation on the protection scope of the present invention. Any simple modification or equivalent replacement of the technical solution of the present invention by those of ordinary skill in the art shall not depart from the essence and scope of the technical solution of the present invention.

Claims

1. A method for determining the constraint boundary of a fault-controlled storage body well, characterized in that It includes the following steps: S1. Obtain the threshold value of the target reservoir detection attribute based on the well-seismic calibration method; S2. Characterize the reservoir body boundary along the fracture direction for the target reservoir; S3. Based on the threshold value of the target reservoir detection attribute obtained in step S1, horizontally characterize the reservoir body boundary along the direction perpendicular to the fracture for the target layer; S4. Based on the reservoir body boundary characterized along the fracture direction and the horizontal characterization of the reservoir body boundary along the direction perpendicular to the fracture, and combined with the spatial attribute of the target reservoir detection attribute, form a three-dimensional data volume spatial visualization display map.

2. The method for determining the constraint boundary of the disconnected control storage collective well according to claim 1, wherein S2 specifically includes the following steps: S201. Extract the fracture detection attribute of the target reservoir; S202. Conduct fracture segmentation difference analysis according to the fracture profile style and plane distribution law, and preliminarily divide those with the same corresponding fracture profile style and plane distribution law into the same reservoir body; S203. Investigate the production dynamic situation of the drilled wells in the target reservoir and the connectivity of the reservoir bodies at different positions, and determine whether they are the same reservoir body according to the dynamic response of the drilled wells; S204. Determine the reservoir body boundary along the fracture direction through the analysis results of steps S202 and S203.

3. The method for determining the constraint boundary of the broken control and storage collective well according to claim 2, characterized in that The fracture profile styles in step S202 at least include negative flower-shaped, positive flower-shaped, translational, and compression ridge.

4. A method for determining the constraint boundary of a disconnected control and storage collective well according to claim 3, characterized in that, The plane distribution laws of step S202 at least include left-lateral left-stepped tensile segment, left-lateral right-stepped compressive segment, linear translational segment, and oblique weak compressive segment.

5. A method for determining the constraint boundary of a fault control and storage collective well according to claim 4, characterized in that The negative flower-shaped fracture profile style corresponds to the plane distribution law of the left-lateral left-stepped tensile segment, the positive flower-shaped fracture profile style corresponds to the plane distribution law of the left-lateral right-stepped compressive segment, the translational fracture profile style corresponds to the plane distribution law of the linear translational segment, and the compression ridge fracture profile style corresponds to the plane distribution law of the oblique weak compressive segment.

6. The method for determining the constraint boundary of the fault-control storage collective well according to claim 2, characterized in that, The specific determination method of S204 is: when the dynamics of different drilled wells within the reservoir body set in step S202 affect each other, it is set as the same reservoir body; when the dynamics of the drilled wells within the reservoir body set in step S202 do not affect each other, it is set as different reservoir bodies.

7. A method for determining the constraint boundary of a disconnected control storage collective well according to claim 1, characterized in that, S1 specifically includes the following steps: S101. Set the threshold value of the cave-like reservoir; S102. Set the threshold value of the pore-like reservoir; S103. Set the threshold value of the fracture-type reservoir.

8. A method for determining the constraint boundary of a fault-controlled storage body well according to claim 7, characterized in that, The specific method of step S101 is: Through the analysis and comparison of the instantaneous energy attribute under different three-dimensional and processing methods, calibrate with the logging interpretation test class I reservoir or the spatial position of the blowout and leakage, and the calibration result is the threshold value of the cave-like reservoir.

9. The method for determining the constraint boundary of the broken control storage collective well according to claim 8, characterized in that, The threshold value of the cave-like reservoir is: the instantaneous energy attribute value is greater than the first set value.

10. A method for determining the constraint boundary of a fault-controlled storage collective well according to claim 7, characterized in that The specific method of step S102 is: Through the normalized comparison analysis of the seismic discontinuity attribute, calibrate with the logging interpretation test class II reservoir or the spatial position of the drilling micro-leakage, and the calibration result is the threshold value of the pore-like reservoir.

11. A method for determining the constraint boundary of a disconnected control storage collective well according to claim 10, characterized in that, The threshold value of the pore-like reservoir is: the seismic discontinuity attribute value is greater than the second set value.

12. A method for determining the constraint boundary of a fault-controlled reservoir collective well according to claim 7, characterized in that, The specific method of step S103 is: Through the normalized comparison analysis of the coherence attribute, calibrate with the spatial position of the logging interpretation class III reservoir, and the calibration result is the threshold value of the fracture-type reservoir.

13. A method for determining the constraint boundary of a disconnected control storage collective well according to claim 12, characterized in that, The threshold value of the fracture-type reservoir is: the coherence attribute is greater than the third set value.

14. A method for determining the constraint boundary of a fault-controlled storage collective well according to claim 7, characterized in that Step S3 specifically includes the following steps: S301. Identify the planar position of the cave-like reservoir according to the threshold value of the cave-like reservoir; S302. Identify the planar position of the pore-like reservoir according to the threshold value of the pore-like reservoir; S303. Identify the planar position of the fracture-type reservoir according to the threshold value of the fracture-type reservoir; S304. Superimpose the identified planar position boundaries of the cave-like reservoir, the planar position boundaries of the pore-like reservoir, and the planar position boundaries of the fracture-type reservoir to form the lateral reservoir boundary of the target reservoir along the vertical fracture direction.

15. A method for determining the constraint boundary of a fault-control storage collective well according to claim 1, characterized in that The spatial attributes of the detected attributes in Step S4 include at least the spatial abscissa, ordinate, depth, and amplitude.

16. A system for using the method according to any one of claims 1-15 to determine the constraint boundary of a fault-controlled reservoir collective well, characterized in that, It includes a first module, a second module, a third module, and a fourth module connected in sequence. The first module is used to execute the content in Step S1, the second module is used to execute the content in Step S2, the third module is used to execute the content in Step S3, and the fourth module is used to execute the content in Step S4.

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