A method and device for quantitatively determining the destructive effect of fracture on the sealing property of caprock

Abstract

The present application discloses a method and device for quantitatively determining the destructive effect of a fault on the sealing property of a cap rock, and relates to the field of oil and gas field exploration. The method includes obtaining petroleum seismic exploration data of the area to be predicted; determining a set of fault position information that will have a destructive effect on the cap rock after reservoir formation based on the petroleum seismic exploration data of the area to be predicted; constructing a three-dimensional fault and cap rock model, and coupling the two based on the destructive fault position information to obtain a cap rock and fault coupling structural model; obtaining a cap rock damage index of the area to be predicted based on the cap rock and fault coupling structural model; determining the degree of destructive effect of a fault on the sealing property of the cap rock in the area to be predicted based on the cap rock damage index of the area to be predicted. The present application realizes a high-precision quantitative evaluation of the destructive effect of a fault on the sealing property of a cap rock, effectively reducing the risk of cap rock evaluation in oil and gas exploration and development, not only improving the accuracy of fault block oil and gas reservoir evaluation, but also providing strong support for the formulation of subsequent development strategies for oil and gas fields.

Description

Technical Field

[0001] The present application relates to the field of oil and gas field exploration, and in particular to a method and device for quantitatively determining the destructive effect of a fracture on the sealing property of a cap rock. Background Art

[0002] The practice of oil and gas exploration in the world shows that after oil and gas accumulate to form oil and gas reservoirs, they will be affected by the reactivation of faults. Existing studies have shown that if the intensity of fault reactivation is large after oil and gas accumulation, the sealing performance of the direct cap rock of the oil and gas reservoir is likely to be destroyed, which will cause the destruction of the accumulated oil and gas reservoirs. The study of this issue is one of the key studies in oil and gas exploration in fault-developed areas of oil and gas basins.

[0003] In related technologies, geological research uses factors such as fault throw, mudstone cap thickness, fault rock displacement pressure, and mudstone cap rock displacement pressure to study the destructive effect of faults on the closure of mudstone caps. However, these factors have certain limitations and cannot fully and accurately reflect the complex effects of faults on the closure of caps. At the same time, with the continuous advancement of oil exploration technology, three-dimensional seismic data plays an increasingly important role in oil and gas exploration and development. It carries rich geological information and provides a new perspective for in-depth research on the closure of caps.

[0004] Nowadays, with the continuous innovation of oil and gas exploration technology and the widespread application of 3D seismic data, the prospect of more accurate evaluation of the sealing property of oil and gas reservoir caprock under the influence of faults has emerged. However, how to effectively use these advanced technologies and data to accurately evaluate the actual impact of faults on the sealing property of caprocks is still a key issue to be solved in the current oil and gas exploration field. Therefore, it is urgent to develop a method that can fully utilize the information of 3D seismic data to achieve a comprehensive and accurate evaluation of the sealing property of oil and gas reservoir caprock under the influence of faults. Summary of the invention

[0005] The purpose of this application is to provide a method and device for quantitatively determining the destructive effect of fractures on the sealing property of cap rocks, which can achieve high-precision quantitative evaluation of the sealing property of cap rocks and effectively reduce the risks in oil and gas exploration and development.

[0006] To achieve the above objectives, this application provides the following solutions:

[0007] In a first aspect, the present application provides a method for quantitatively determining the destructive effect of a fracture on the sealing property of a caprock, comprising:

[0008] Obtaining petroleum seismic exploration data for the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation;

[0009] Determine a set of location information of a destructive fault according to the petroleum seismic exploration data of the area to be predicted; the set of location information of the destructive fault includes at least one piece of location information of a destructive fault; the location information of the destructive fault is the spatial position of a fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir;

[0010] Based on the fault plane interpretation data and the target cap rock section plane interpretation data in the petroleum seismic exploration data of the predicted area, a three-dimensional fault plane model and a three-dimensional cap rock plane model are constructed respectively;

[0011] Based on the set of damaged fault position information, a three-dimensional cap layer model and a three-dimensional fault layer model are coupled to construct a cap layer and fault coupled structural model;

[0012] Based on the coupled structural model of cap rock and fault, the cap rock damage index of the area to be predicted is obtained;

[0013] According to the cap rock damage index of the area to be predicted, the degree of damage to the sealing property of the cap rock by the fault in the area to be predicted is determined.

[0014] In a second aspect, the present application provides a device for quantitatively determining the destructive effect of a fracture on the sealing property of a caprock, comprising:

[0015] A data acquisition module is used to obtain petroleum seismic exploration data of the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation;

[0016] A damage fault position identification module is used to determine a damage fault position information set based on the petroleum seismic exploration data of the area to be predicted; the damage fault position information set includes at least one piece of damage fault position information; the damage fault position information is the spatial position of the fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir;

[0017] A three-dimensional model building module is used to build a three-dimensional fault layer model and a three-dimensional cap layer model based on the fault layer interpretation data and the target cap layer layer interpretation data in the petroleum seismic exploration data of the area to be predicted;

[0018] A coupled structural model generation module is used to couple the three-dimensional cap layer model and the three-dimensional fault layer model based on the set of damaged fault position information to construct a coupled structural model of the cap layer and the fault;

[0019] The module for calculating the cap rock damage index is based on the cap rock and fault coupling structural model to obtain the cap rock damage index of the area to be predicted;

[0020] The destructive effect determination module is used to determine the degree of destructive effect of the fault in the area to be predicted on the sealing property of the cap rock according to the cap rock damage index of the area to be predicted.

[0021] According to the specific embodiments provided in this application, this application has the following technical effects:

[0022] The present application provides a method and device for quantitatively determining the destructive effect of a fault on the sealing property of a cap rock. By acquiring the petroleum seismic exploration data of the area to be predicted, the problem of missing basic data is solved, a comprehensive understanding of the geological targets in the area to be predicted is achieved, and reliable data support is provided for subsequent analysis. By determining the destructive fault position information set and the fault plane interpretation data and the target cap rock section plane interpretation data in the petroleum seismic exploration data of the area to be predicted based on the petroleum seismic exploration data of the area to be predicted, a three-dimensional fault plane model and a three-dimensional cap rock plane model are constructed respectively, the problems of unclear destructive fault position and difficult intuitive display of geological structure are solved, accurate positioning of the destructive fault position and three-dimensional visual modeling of geological evaluation targets are achieved, and a basis for subsequent coupled analysis is provided. The fault position information is collected, and the three-dimensional cap layer model and the three-dimensional fault layer model are coupled to construct a cap layer and fault coupling structural model, which solves the problem that the relationship between faults and cap layers is difficult to comprehensively analyze, realizes the intuitive display and comprehensive analysis of faults and cap layers in three-dimensional space, and provides a basis for evaluating the degree of cap layer fragmentation; based on the cap layer and fault coupling structural model, combined with the chaos index and fractal index of the complex structure in the cap layer segment, the complex fragmentation structure parameters of the cap layer segment in the predicted area are obtained, which solves the problem that the degree of cap layer fragmentation is difficult to quantify, realizes the quantitative evaluation of the degree of cap layer fragmentation, and provides a key indicator for judging the sealing of the cap layer; by determining the degree of destructive effect of the faults in the predicted area on the sealing of the cap layer according to the cap layer damage index of the predicted area, it provides strong decision-making support for oil and gas exploration and development. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Picture 1 A schematic flow chart of a method for quantitatively determining the destructive effect of a fracture on the sealing property of a cap rock provided in one embodiment of the present application.

[0025] Picture 2This is an application effect diagram of a cap layer damage index CFI provided in one embodiment of the present application.

[0026] Picture 3 A schematic diagram of the functional modules of a device for quantitatively determining the destructive effect of a fracture on the sealing property of a caprock provided in one embodiment of the present application. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0029] In an exemplary embodiment, Picture 1 As shown, a method for quantitatively determining the destructive effect of a fracture on the sealing property of a cap rock is provided, comprising the following steps 101 to 106. Among them:

[0030] Step 101, obtaining petroleum seismic exploration data of the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation.

[0031] Step 102, determining a set of destructive fault location information based on the petroleum seismic exploration data of the area to be predicted; the destructive fault location information set includes at least one piece of location information of a destructive fault; the location information of the destructive fault is the spatial position of a fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir.

[0032] Step 103, based on the fault plane interpretation data and the target cap rock section plane interpretation data in the petroleum seismic exploration data of the area to be predicted, construct a three-dimensional fault plane model and a three-dimensional cap rock plane model respectively.

[0033] Step 104, based on the set of damaged fault location information, the three-dimensional cap layer model and the three-dimensional fault layer model are coupled to construct a cap layer and fault coupled structural model.

[0034] Step 105: Based on the coupled structural model of the cap rock and the fault, obtain the cap rock damage index of the area to be predicted.

[0035] Step 106, determining the degree of damage to the sealing property of the caprock by the faults in the area to be predicted based on the caprock damage index of the area to be predicted.

[0036] By implementing the above steps 101 to 106, the present application not only improves the accuracy and reliability of the degree of damage caused by fractures to the sealing property of the cap rock, but also provides a more efficient and scientific evaluation method for oil and gas exploration and development.

[0037] In another exemplary embodiment of the present application, step 102 specifically includes:

[0038] The stratigraphic thickness of the downthrown plate, the stratigraphic thickness of the upthrown plate and the fault throw of the fault in the predicted area are determined based on the fault plane interpretation data, the target cap rock section plane interpretation data and the geological age data of the formation in the predicted area.

[0039] The fracture growth index of each fault in the predicted area is obtained according to the ratio of the thickness of the downthrown plate to the thickness of the upthrown plate in the predicted area.

[0040] The reactivated fault distance is obtained by subtracting the fault distance of the predicted area from the ancient fault distance in the strata during the oil and gas accumulation period. The ancient fault distance in the strata during the oil and gas accumulation period is obtained by the vertical fault distance subtraction method.

[0041] According to the petroleum seismic exploration data of the area to be predicted, the location information of each fault is obtained, and according to the fault growth index and reactivated fault distance of each fault in the area to be predicted, the initial fault set is obtained.

[0042] The location information of the faults in the initial fault set whose fracture growth index is greater than 1 and whose reactivated fault distance is greater than the preset fault distance threshold is added to the damaged fault location information set. In petroleum geological research, the fracture growth index is a key indicator for evaluating the activity of fractures. Its calculation is based on the ratio of the formation thickness of the downthrown plate to the upthrown plate, and the fracture growth index can be calculated. When the index is equal to 1, it indicates that the fracture has not been reactivated after the oil and gas accumulation; when the index is greater than 1 and the reactivated fault distance is greater than the preset fault distance threshold, it indicates that the fracture has been reactivated, thereby determining which fractures have a destructive effect on the caprock. Formation thickness and fracture growth index can be further calculated based on petroleum seismic exploration data.

[0043] In another exemplary embodiment of the present application, step 104 specifically includes:

[0044] Based on the set of damage fault position information, the damage fault position is hollowed out in the three-dimensional cap layer model, and filled with data corresponding to the damage fault position in the three-dimensional fault layer model to construct a cap layer and fault coupling structural model.

[0045] In another exemplary embodiment of the present application, the above step 105 is replaced by the following steps 201 to 203:

[0046] Step 201, based on the coupled structural model of the cap rock and fault, obtain the complex fracture structure parameter (complex index, CI) of the cap rock segment in the area to be predicted.

[0047] Step 202, obtain the distribution data of the reactivation rate of the fault and the mud content of the cap rock in the plane after the oil and gas accumulation in the predicted area. The definition of the reactivation rate of the fault is the reactivation fault distance of the fault divided by the geological time of the reactivation of the fault. The higher the reactivation rate Va of the fault after the oil and gas accumulation, the stronger the fault activity, the greater the destructive effect of the fault on the cap rock, and the worse the sealing ability of the cap rock; the lower the reactivation rate Va. As mentioned above, when the index is greater than 1, it indicates that the fault has reactivated, and the reactivation fault distance needs to be further calculated along the fault strike. The reactivation fault distance of the fault should be equal to the fault distance in the current formation minus the ancient fault distance in the formation during the oil and gas accumulation period. The calculation of the ancient fault distance can be obtained by the vertical fault distance subtraction method. The higher the mud content of the cap rock section, the stronger the sealing ability of the cap rock; and the higher the sandstone content in the cap rock, the weaker the sealing ability of the cap rock, because the permeability of sandstone is stronger and sandstone is more likely to break and produce cracks and micro fractures. The distribution data of the mud content of the cap rock in the plane are obtained through seismic inversion data. The formation thickness, fault throw and paleo-fault throw are further calculated based on the petroleum seismic exploration data.

[0048] Step 203, obtaining the caprock fracturing index (CFI) of the area to be predicted based on the complex fracture structure parameters of the current caprock segment of the area to be predicted, the reactivation rate of the fault after oil and gas accumulation, and the planar distribution data of the caprock shale content.

[0049] As an optional implementation, step 201 specifically includes:

[0050] Based on the coupled structural model of cap rock and fault, the strike direction of each fault in the area to be predicted is determined.

[0051] A preset sliding window is set along the strike of each fault.

[0052] In each preset sliding window, the chaos index and fractal index of each fault are calculated respectively; wherein the chaos index and fractal index are obtained based on the post-stack three-dimensional seismic processing results data of the petroleum seismic exploration data in the area to be predicted.

[0053] According to the calculated chaos index and fractal index of each fault, the complex fragmentation structure parameters of the cap rock segment in the area to be predicted are obtained.

[0054] Among them, by implementing this implementation method, the complex broken structure parameters of the cap rock section in the area to be predicted are obtained according to the calculated chaos index and fractal index of each fault, which specifically include:

[0055] If the chaos index is greater than or equal to 1, the complex fracture structure parameters of the caprock section are:

[0056] .

[0057] If the chaos index is greater than 0 and less than 1, the complex fracture structure parameters of the caprock section are:

[0058] .

[0059] in, CI Indicates the complex crushing structure parameters of the caprock segment, L represents the chaos index, D I Represents the fractal index.

[0060] In summary, CI The construction of is based on the coupled structural model of caprock and fault and oil seismic exploration data, and is the chaos index of oil seismic exploration data in the caprock section. L , Fractal Index DI Specifically, a constraint window with a certain thickness range is agreed upon according to the thickness of the cap layer, and then the chaos index of the oil seismic exploration data within the constraint window is calculated along the coupled structural model of the cap layer and the fault. L , Fractal Index D I .

[0061] Finally, the complex combined structure of the caprock segment should be extracted by level-by-level constraints. The specific process is as follows:

[0062] The implementation of step-by-step constraints on the complex combined structure of the caprock section is based on the chaos index L in the seismic data. The specific constraints are as follows:

[0063] (1) When L >=1, which means that the network complexity of the combined structure of faults and cracks in the cap layer is high, corresponding to the highly complex waveform in the seismic wave, which means that the risk of cap layer damage is increased and the sealing is reduced. CI Chaos Index L Fractal Index D I The product of .

[0064] (2) When 0< L<1, which means that the network complexity of the combined structure of faults and cracks inside the cap layer is low, corresponding to the seismic waveform with low complexity, which means that the risk of cap layer damage is reduced and the sealing is increased. CI The construction of takes the following form: Chaos Index L It is an important concept in the field of chaos theory and dynamic systems. It is one of the numerical characteristics for identifying chaotic motion. Here, the Lyapunov index (Lyapunov characteristic index) is used to represent the chaotic characteristics in oil seismic data. It is a representation of the chaotic characteristics of complex structures caused by fractures and cracks in the caprock. It is dimensionless. Regarding the judgment of chaos, if the maximum chaos index of a system is L If it is greater than zero, the system exhibits chaotic phenomena, indicating that the system is complex and nonlinear; otherwise, the system is simple and linear.

[0065] Information dimension is a key concept in fractal geometry, which quantifies the amount of information and complexity of fractal structures through specific formulas. It captures the irregularity and complexity inside the fractal structure. In practical applications, information dimension is used as a tool to distinguish the characteristics of different fractal structures. It is particularly helpful to identify and analyze complex structures in the caprock, such as the fault zone inside the caprock, which can be regarded as a complex network structure caused by factors such as fractures and cracks, which are the result of the internal response of the caprock. Information dimension can be calculated by the box-counting method.

[0066] Among them, in this implementation method, the calculation formula of the chaos index is:

[0067] .

[0068] in, t Indicates the position of any post-stack 3D seismic processing result data on the fault surface. represents the distance between two seismic wave traces x(t) and y(t) at position t, Represents the distance between the two seismic wave traces x(0) and y(0) at the starting reference position.

[0069] The calculation formula of the fractal index is:

[0070] .

[0071] .

[0072] in, Indicates the minimum sliding window unit used in fractal measurement. I represents information entropy, pi Indicates that the fault is i The probability of a preset sliding window being observed.

[0073] As an optional implementation, step 203 specifically includes:

[0074] .

[0075] From the above mentioned factors and parameters analysis, CFI The index is composed of multiple parameters that affect the sealing quality of the caprock, and is combined with the complex fragmentation structure parameters of the caprock segment composed of faults and cracks. CI , the rate of reactivation of faults after oil and gas accumulation Va Proportional to the distribution data of the mud content of the caprock on the plane vsh Inversely proportional.

[0076] If the chaos index is greater than or equal to 1, the caprock damage index is:

[0077] .

[0078] If the chaos index is greater than 0 and less than 1, the caprock damage index is:

[0079] .

[0080] in, CFI represents the caprock damage index, L represents the chaos index, D I represents the fractal index, Va It indicates the rate of fault reactivation after oil and gas accumulation, which is the ratio of the fault distance caused by the reactivation of the fault after the accumulation to the corresponding geological age interval; vsh Represents the distribution data of the mud content of the cap rock on the plane.

[0081] In another exemplary embodiment of the present application, step 106 specifically includes:

[0082] The degree of damage to the caprock sealing property of the faults in the predicted area is determined based on the absolute value of the difference between the caprock damage index of the predicted area and the preset damage index threshold; the preset damage index threshold is determined based on the lithology inversion data, oil and gas well logging interpretation data and oil and gas test results data in the petroleum seismic exploration data of the predicted area and adjacent areas. CFI , it can be calibrated according to the presence or absence of oil and gas reservoirs (oil and gas displays) CFI The lower threshold is the area to be predicted. CFI Data and CFIBy comparing the lower thresholds, the sealing performance of the cap rock to oil and gas can be quantitatively evaluated, and favorable locations and locations with the risk of cap rock damage can be determined.

[0083] The area to be predicted CFI Value and CFI The lower threshold comparison, where if the area to be predicted CFI If the value is larger than the lower limit of the sealing value, the cap layer is highly damaged and the sealing property of the cap layer in the corresponding part becomes worse; on the contrary, if the cap layer is less damaged, the sealing property of the cap layer in the corresponding part is strong.

[0084] Specifically, the sealing capacity of each test point of the cover layer is CFI The difference between the fault value and the lower limit of the sealing value indicates that if the difference is larger, the destructive effect of the fault on the cap rock is stronger and the sealing property of the cap rock is weaker, and vice versa.

[0085] Taking a tension-type normal fault in a basin in the eastern part of a country as an example, the effect of this application is described. Picture 2 As shown in the figure. It is found that the degree of damage to the cap rock by different faults varies greatly, and there are also obvious differences in different parts of the same fault zone. This change reflects the difference in the damage effect of faults on the cap rock. Specifically, combined with the distribution of oil and gas layers and oil and gas wells in the area, it is statistically believed that 116 is the CFI The lower limit of the index threshold, the region CFI Index greater than 116 belongs to CFI The high-value area is an area where the caprock is severely damaged, which is not conducive to the preservation of oil and gas; it can be used as a location for oil and gas to migrate vertically upward along the fault; CFI Index less than 116 indicates that the sealing property of the caprock is improved. CFI Combined with the oil and gas distribution, further analysis shows that Picture 2 Zhongtan Well A CFI The high-value area indicates that the cap rock is severely damaged, and it is speculated that the possibility of discovering oil and gas in the strata above the cap rock is greater; the area near Well B and Well C CFI The low value is more widely distributed, and the caprock plays a good sealing role. It is speculated that the strata below the caprock are more conducive to oil and gas accumulation; the oil and gas exploration results confirm that well A found good oil and gas shows in the geological strata above the caprock, and wells B and C had no oil and gas shows in the strata above the caprock, but wells B and C found oil and gas below the caprock. The prediction results are consistent with drilling practice, indicating that the application effect of this application conforms to geological laws and is reliable.

[0086] The beneficial effect of the present application is that the complex crushing structure parameters of the cap rock segment with the combined structure of fractures and cracks in the cap rock segment are constructed. CI , combined with the mud content of the caprock vsh , fracture reactivation rate Va , a caprock damage index was proposed CFI The construction method objectively reflects the influence of geological elements such as fault activity, cracks, mud content on the cap rock, so as to achieve the purpose of quantitatively evaluating the vertical sealing ability of the cap rock and determining favorable sealing positions; this application is mainly based on seismic data, which is more objective and rapid, and the evaluation effect brought by this application is more in line with actual geological laws.

[0087] The present application also provides an application scenario, which applies the above-mentioned method for quantitatively determining the destructive effect of fractures on the sealing property of cap rocks. Specifically: the method for quantitatively determining the destructive effect of fractures on the sealing property of cap rocks provided in this embodiment can be applied in oil and gas field exploration and development scenarios. The oil and gas field exploration and development scenario includes a data acquisition link, a data analysis and processing link, and a decision-making link; geological data enters the data analysis and processing link from the data acquisition link, and after a series of analysis and calculation, the sealing property assessment result of the cap rock is obtained, and enters the downstream decision-making link. The method for quantitatively determining the destructive effect of fractures on the sealing property of cap rocks provided in this embodiment belongs to the cap rock sealing property assessment sub-link in the data analysis and processing link. Specifically, in the process of geological data analysis and processing for oil and gas fields, the influence of fractures on the sealing property of cap rocks can be quantitatively determined based on this method, providing a basis for subsequent oil and gas field development decisions.

[0088] Based on the same inventive concept, the embodiment of the present application also provides a device for quantitatively determining the destructive effect of a fracture on the sealing property of a cap layer for realizing the method for quantitatively determining the destructive effect of a fracture on the sealing property of a cap layer involved in the above-mentioned method. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above-mentioned method, so the specific limitations in the embodiments of one or more devices for quantitatively determining the destructive effect of a fracture on the sealing property of a cap layer provided below can refer to the limitations of the method for quantitatively determining the destructive effect of a fracture on the sealing property of a cap layer above, and will not be repeated here.

[0089] In an exemplary embodiment, Picture 3 As shown, a device for quantitatively determining the destructive effect of a fracture on the sealing property of a cap rock is provided, comprising:

[0090] The data acquisition module 301 is used to obtain the petroleum seismic exploration data of the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation.

[0091] The destructive fault position identification module 302 is used to determine a destructive fault position information set based on the petroleum seismic exploration data of the area to be predicted; the destructive fault position information set includes at least one destructive fault position information; the destructive fault position information is the spatial position of the fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir.

[0092] The three-dimensional model building module 303 is used to build a three-dimensional fault plane model and a three-dimensional cap layer model respectively based on the fault plane interpretation data and the target cap layer section plane interpretation data in the petroleum seismic exploration data of the area to be predicted.

[0093] The coupled structural model generating module 304 is used to couple the three-dimensional cap layer model and the three-dimensional fault layer model based on the set of damaged fault position information to construct a coupled structural model of the cap layer and the fault.

[0094] The cover layer damage index calculation module 305 obtains the cover layer damage index of the area to be predicted based on the cover layer and fault coupling structural model.

[0095] The destructive effect determination module 306 is used to determine the degree of destructive effect of the faults in the area to be predicted on the sealing property of the caprock according to the caprock damage index of the area to be predicted.

[0096] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0097] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for quantitatively determining the destructive effect of a fracture on the sealing property of a caprock, characterized in that: The quantitative determination method of the damage effect of the fracture on the sealing property of the cap rock includes: Obtaining petroleum seismic exploration data for the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation; Determine a set of location information of a destructive fault according to the petroleum seismic exploration data of the area to be predicted; the set of location information of the destructive fault includes at least one piece of location information of a destructive fault; the location information of the destructive fault is the spatial position of a fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir; Based on the fault plane interpretation data and the target cap rock section plane interpretation data in the petroleum seismic exploration data of the predicted area, a three-dimensional fault plane model and a three-dimensional cap rock plane model are constructed respectively; Based on the set of damaged fault position information, a three-dimensional cap layer model and a three-dimensional fault layer model are coupled to construct a cap layer and fault coupled structural model; Based on the coupled structural model of cap rock and fault, the cap rock damage index of the area to be predicted is obtained, specifically including: based on the coupled structural model of cap rock and fault, the complex broken structural parameters of the cap rock section in the area to be predicted are obtained; the distribution data of the reactivation rate of the faults after the oil and gas accumulation in the area to be predicted and the mud content of the cap rock on the plane are obtained; based on the complex broken structural parameters of the current cap rock section in the area to be predicted, the reactivation rate of the faults after the oil and gas accumulation and the distribution data of the mud content of the cap rock on the plane are obtained; The method of obtaining the complex broken structure parameters of the cap rock segment in the area to be predicted based on the cap rock and fault coupled structure model specifically includes: determining the strike of each fault in the area to be predicted based on the cap rock and fault coupled structure model; setting a preset sliding window along the strike of each fault; calculating the chaos index and fractal index of each fault within each preset sliding window; wherein the chaos index and fractal index are obtained based on the post-stack three-dimensional seismic processing result data in the petroleum seismic exploration data in the area to be predicted; obtaining the complex broken structure parameters of the cap rock segment in the area to be predicted based on the calculated chaos index and fractal index of each fault; According to the cap rock damage index of the area to be predicted, the degree of damage to the sealing property of the cap rock by the fault in the area to be predicted is determined.

2. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 1, characterized in that: According to the oil seismic exploration data of the area to be predicted, the location information set of the damaged fault is determined, including: Determine the stratigraphic thickness of the downthrown plate, the stratigraphic thickness of the upthrown plate and the fault throw of the fault area to be predicted based on the fault plane interpretation data, the target cap rock section plane interpretation data and the geological age data of the formation in the petroleum seismic exploration data of the area to be predicted; The fracture growth index of each fault in the predicted area is obtained according to the ratio of the thickness of the downthrown plate of the fault in the predicted area to the thickness of the upthrown plate; The reactivated fault distance is obtained by subtracting the fault distance of the predicted area from the ancient fault distance in the strata during the oil and gas accumulation period; the ancient fault distance in the strata during the oil and gas accumulation period is obtained by the vertical fault distance subtraction method; According to the petroleum seismic exploration data of the area to be predicted, the location information of each fault is obtained, and according to the fault growth index and reactivated fault distance of each fault in the area to be predicted, the initial fault set is obtained; The position information of the faults in the initial fault set whose fracture growth index is greater than 1 and whose reactivated fault throw is greater than a preset fault throw threshold is added to the destroyed fault position information set.

3. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 1, characterized in that: Based on the set of damaged fault location information, a three-dimensional cap layer model and a three-dimensional fault layer model are coupled to construct a cap layer and fault coupled structural model, which specifically includes: Based on the set of damage fault position information, the damage fault position is hollowed out in the three-dimensional cap layer model, and filled with data corresponding to the damage fault position in the three-dimensional fault layer model to construct a cap layer and fault coupling structural model.

4. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 1, characterized in that: According to the calculated chaos index and fractal index of each fault, the complex fragmentation structure parameters of the cap rock section in the predicted area are obtained, including: If the chaos index is greater than or equal to 1, the complex fracture structure parameters of the caprock section are: ； If the chaos index is greater than 0 and less than 1, the complex fracture structure parameters of the caprock section are: ； in, CI Indicates the complex crushing structure parameters of the caprock segment, L represents the chaos index, D I Represents the fractal index.

5. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 4, characterized in that: The calculation formula of chaos index is: ； in, t Indicates the position of any post-stack 3D seismic processing result data on the fault surface. Indicates at location t The distance between the two seismic wave traces x(t) and y(t) is represents the distance between the two seismic wave traces x(0) and y(0) at the starting reference position; The calculation formula of the fractal index is: ； ； in, Indicates the minimum sliding window unit used in fractal measurement. I represents information entropy, p i Indicates that the fault is i The probability of a preset sliding window being observed.

6. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 1, characterized in that: According to the cap rock damage index of the area to be predicted, the degree of damage to the cap rock sealing of the fault in the area to be predicted is determined, including: The degree of damage to the sealing property of the cap rock caused by the faults in the predicted area is determined based on the absolute value of the difference between the cap rock damage index of the predicted area and a preset damage index threshold; the preset damage index threshold is determined based on the lithology inversion data body, oil and gas well logging interpretation data and oil and gas test results data statistics in the petroleum seismic exploration data of the discovered oil and gas reservoirs in the predicted area and the adjacent areas.

7. The method for quantitatively determining the destructive effect of fracture on the sealing property of caprock according to claim 1, characterized in that: According to the complex broken structure parameters of the cap rock section in the predicted area, the reactivation rate of the fault after oil and gas accumulation and the distribution data of the cap rock mud content on the plane, the cap rock damage index of the predicted area is obtained, which includes: If the chaos index is greater than or equal to 1, the caprock damage index is: ； If the chaos index is greater than 0 and less than 1, the caprock damage index is: ； in, CFI represents the caprock damage index, L represents the chaos index, D I represents the fractal index, V It indicates the rate of fault reactivation after oil and gas accumulation, which is the ratio of the fault distance caused by the reactivation of the fault after accumulation to the corresponding geological age interval; vsh Represents the distribution data of the mud content of the cap rock on the plane.

8. A device for quantitatively determining the destructive effect of fracture on the sealing property of caprock, characterized in that: The quantitative determination device of the destructive effect of a fracture on the sealing property of a cap rock is applied with the quantitative determination method of the destructive effect of a fracture on the sealing property of a cap rock as claimed in any one of claims 1 to 7, and the quantitative determination device of the destructive effect of a fracture on the sealing property of a cap rock comprises: A data acquisition module is used to obtain petroleum seismic exploration data of the area to be predicted; the petroleum seismic exploration data includes post-stack three-dimensional seismic processing results data, lithology inversion data body, fault layer interpretation data, target cap rock layer layer interpretation data, oil and gas well logging interpretation data, oil and gas test results data, and geological age data of the formation; A damage fault position identification module is used to determine a damage fault position information set based on the petroleum seismic exploration data of the area to be predicted; the damage fault position information set includes at least one piece of damage fault position information; the damage fault position information is the spatial position of the fault that becomes active and has a destructive effect on the cap rock of the oil and gas reservoir after the oil and gas accumulate to form a reservoir; A three-dimensional model building module is used to build a three-dimensional fault layer model and a three-dimensional cap layer model based on the fault layer interpretation data and the target cap layer layer interpretation data in the petroleum seismic exploration data of the area to be predicted; A coupled structural model generation module is used to couple the three-dimensional cap layer model and the three-dimensional fault layer model based on the set of damaged fault position information to construct a cap layer and fault coupled structural model; The module for calculating the cap rock damage index is based on the cap rock and fault coupling structural model to obtain the cap rock damage index of the area to be predicted; The destructive effect determination module is used to determine the degree of destructive effect of the fault in the area to be predicted on the sealing property of the cap rock according to the cap rock damage index of the area to be predicted.

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