Evaluation method and system for transport capacity of static oil source faults during reservoir formation

Abstract

The present invention belongs to the field of oil and gas geological exploration, and relates to a method and system for evaluating the conductivity of static oil source faults during the reservoir formation period. The method steps are: determining the longitudinal cutting layer system of the fault, judging whether the fault is an oil source fault according to whether the fault cuts the underlying hydrocarbon source rock; calculating the fault distance of each oil source fault; calculating the fault fracture zone identification parameters, and identifying the upper and lower plate induced fracture zones according to the fault fracture zone identification parameters; performing correlation analysis to obtain the linear relationship between the induced fracture zone widths of the upper and lower plates, and the linear relationship between the sum of the induced fracture zone widths and the fault distance; calculating the induced fracture zone widths of the upper and lower plates according to the linear relationship, and evaluating the conductivity of the fault for oil and gas based on the distribution characteristics of the induced fracture zone widths of the upper and lower plates. The system is used to implement the above method. The present invention can accurately evaluate the conductivity of static oil source faults during the reservoir formation period for oil and gas.

Description

Technical Field

[0001] The present application relates to the technical field of oil and gas geological exploration, and in particular to a method and system for evaluating the transport capacity of static oil source faults during the reservoir formation period. Background Art

[0002] In the vertical migration of oil and gas, faults are of great significance as transport elements. The document "Research on the Structure and Closure of Fault Fracture Zones in Fault Basins [D]. Tan Quanguo. China University of Petroleum (East China), 2019" records that during the development of faults, fault sliding surfaces will be generated in the rocks, and a large number of induced cracks will be generated on both sides, greatly improving the porosity and permeability of the rocks near the faults, thereby improving the oil and gas transport capacity of the faults, effectively identifying the location of large-scale oil and gas migration, and is of great significance for guiding oil and gas exploration deployment and reducing exploration risks.

[0003] In the past, there have been a lot of studies on the identification of fault fracture zones, but there have been few studies on the relationship between fault scale and the development characteristics and width of the fault zone. At present, the main methods for dividing the structure of fault fracture zones are:

[0004] (1) The document "Logging methods and research progress for identification of tight reservoir fractures [J]. Xu Tonghai. Oil and Gas Geology and Recovery, 2005, (03): 75-78+88." used conventional logging methods and imaging logging methods to identify fracture zones. Among them, the resistivity logging curve showed a low value, and the waveform disturbance of the sonic time difference logging curve was large. Imaging logging can be the most intuitive and effective way to identify underground fractures.

[0005] (2) In the literature “Internal structural characteristics of fault zones and their relationship with oil and gas migration and accumulation [J]. Chen Wei, Wu Zhiping, Hou Feng, et al. Acta Petrolei Sinica, 2010, 31(5):7”, the internal structure of the faults was qualitatively divided and conventional logging calibration was performed by using seismic, drilling, and imaging logging data in combination with field division of the fault zones. The logging response characteristics were summarized and quantitatively analyzed using the indicator curve calculation method and the crossplot method.

[0006] (3) The document “Structural Characteristics and Evolution of Yilan Area in Yishu Graben[D]. Rong Weijiang. Jilin University, 2023.” mainly identifies and describes the fault-related structures in the study area based on three-dimensional seismic structural interpretation and structural geometry methods.

[0007] Existing evaluations of fault conductivity mostly focus on studies of faults during their active periods. The characterization of static faults' conductivity for oil and gas during the critical accumulation period is obviously insufficient, which reduces the accurate evaluation of the amount of oil and gas migration along the faults and affects the success rate of drilling. Summary of the invention

[0008] The present application provides a method and system for evaluating the conductivity of oil source faults that are static during the accumulation period, which describes the changes in the width of the induced fracture zones in the upper and lower plates of the oil source fault with the fault distance, and realizes accurate evaluation of the oil and gas conductivity of oil source faults that are static during the accumulation period, so as to at least solve the problem that the prior art is obviously insufficient in describing the conductivity of oil and gas of faults that are static during the key accumulation period.

[0009] In a first aspect, the present application provides a method for evaluating the transport capacity of static oil source faults during the reservoir formation period, comprising the following steps:

[0010] Oil source fault identification steps: determine the vertical cutting layer of the fault based on the existing seismic data results, and judge whether the fault is an oil source fault based on whether the fault cuts the underlying source rock;

[0011] Fault throw calculation steps: Calculate the fault throw of each oil source fault according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line;

[0012] Fault zone identification steps: Calculate fault zone identification parameters based on resistivity and porosity logging parameters of the wells passing through the fault, and identify the upper and lower wall induced fracture zones based on the fault zone identification parameters;

[0013] Correlation analysis steps: fitting the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate to obtain the linear relationship between the widths of the induced fracture zones in the upper and lower plates; fitting the sum of the widths of the induced fracture zones and the fault distance to obtain the linear relationship between the sum of the widths of the induced fracture zones and the fault distance;

[0014] Width calculation steps: according to the distribution characteristics of fault throw in the area where drilling has not yet begun, the widths of the upper and lower plates of the induced fracture zone are calculated according to the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones of the upper and lower plates, and the distribution characteristics of the widths of the upper and lower plates of the induced fracture zone are obtained;

[0015] Evaluation steps: Based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates, the fault's ability to transport oil and gas is evaluated.

[0016] In some embodiments, in the oil source fault identification step, the method for judging whether the fault is an oil source fault is based on whether the fault cuts the underlying source rock: if the fault cuts the underlying source rock, the fault is judged to be an oil source fault, and the fault serves as a channel for vertical transportation of natural gas; if the fault does not cut the underlying source rock, the fault is judged to be an invalid fault, and the fault does not have the ability to vertically transport natural gas.

[0017] In some embodiments, in the fault calculation step, the fault distance of each oil source fault is calculated according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line according to formula (1), and formula (1) is expressed as:

[0018] (1)

[0019] In the formula, is the break distance, is the vertical distance of the seismic section, is the horizontal distance of the seismic profile, is the angle between the fault strike and the survey line.

[0020] In some embodiments, in the fault zone identification step, the fault zone identification parameter is calculated by formula (2), which is expressed as:

[0021] (2)

[0022] In the formula, Identify parameters for fault fracture zones; is the deep lateral resistivity, unit: ; is the shallow lateral resistivity, unit: ; is the acoustic porosity, unit: % is the density porosity, unit: % is the neutron porosity, unit: %.

[0023] In some embodiments, in the fault fracture zone identification step, the specific method for identifying the upper and lower plate induced fracture zones according to the fault fracture zone identification parameters is as follows: if the fault fracture zone identification parameter curve is overall flat and similar to the upper and lower plate surrounding rock curves, it is identified as a sliding fracture zone; if the fault fracture zone identification parameter curve has an overall large variation range and is narrow and peak-shaped in many places, it is identified as an induced fracture zone; the induced fracture zone above the sliding fracture zone is the upper plate induced fracture zone, and the induced fracture zone below the sliding fracture zone is the lower plate induced fracture zone.

[0024] In some embodiments, in the correlation analysis step, the linear relationship between the widths of the induced crack zones of the upper and lower plates is expressed as:

[0025] (3)

[0026] In the formula, is the width of the induced fracture zone in the hanging wall, is the width of the induced fracture zone in the footwall, is the correlation slope, is the correlation intercept;

[0027] The linear relationship between the sum of the induced crack widths and the fault throw is expressed as:

[0028] (4)

[0029] In the formula, The total width of the induced crack zone, is the break distance, is the correlation slope, is the correlation intercept.

[0030] In some embodiments, the sum of the induced fracture zone widths is equal to the induced fracture zone width in the hanging wall plus the induced fracture zone width in the footwall.

[0031] In the second aspect, the present application provides a static oil source fault conductivity evaluation system during the reservoir formation period, comprising:

[0032] Data acquisition module, used to obtain existing seismic data results;

[0033] The oil source fault identification module is used to determine the vertical cutting layer of the fault based on the existing seismic data results, and to judge whether the fault is an oil source fault based on whether the fault cuts the underlying hydrocarbon source rock;

[0034] Measuring device, measuring the vertical distance and horizontal distance of each oil source fault seismic profile and the angle between the fault strike and the survey line;

[0035] A fault distance calculation module calculates the fault distance of each oil source fault according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line;

[0036] The fault zone identification module calculates the fault zone identification parameters based on the resistivity and porosity logging parameters of the fault wells, and identifies the upper and lower plate induced fracture zones based on the fault zone identification parameters;

[0037] The correlation analysis module fits the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate to obtain the linear relationship between the widths of the induced fracture zones in the upper and lower plates; fits the sum of the widths of the induced fracture zone and the fault distance to obtain the linear relationship between the sum of the widths of the induced fracture zone and the fault distance;

[0038] The width calculation module calculates the width of the upper and lower plates of the induced fracture zone according to the distribution characteristics of the fault throw in the area where drilling has not yet begun, based on the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones of the upper and lower plates, and obtains the distribution characteristics of the widths of the induced fracture zones of the upper and lower plates;

[0039] The evaluation module evaluates the fault's ability to transport oil and gas based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates.

[0040] Compared with the related art, the method and system for evaluating the transport capacity of static oil source faults during the reservoir formation period provided by the present application, according to the interpretation results of existing seismic data (structural interpretation results of three-dimensional seismic data), identifies the location of the oil source fault, and characterizes the fault distance characteristics of faults at different locations, and obtains the fault distances of different locations of each oil source fault; selects the well position passing through the fault, calculates the fault fault zone identification parameters according to the logging data of the well passing through the fault, divides different types of fault zones according to the fault fault zone identification parameters, and characterizes the width characteristics of the induced fracture zones of the upper and lower plates; analyzes the correlation between the fault fault distance and the width of the induced fracture zones of the upper and lower plates, and quantitatively characterizes the development characteristics of the induced fracture zones of faults at different locations according to the correlation analysis results. The method and system of the present invention realize the evaluation of the transport capacity of static oil source faults during the reservoir formation period, solves the problem that it was difficult to evaluate the transport capacity of static oil source faults during the reservoir formation period in the past, makes the migration capacity of early faults for oil and gas more in line with the actual geological conditions, and makes the evaluation results more accurate. It can also further predict the amount of oil and gas migration and the favorable migration direction, and effectively reduces the drilling risk.

[0041] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0043] Figure 1 It is a flow chart of the method for evaluating the conductivity of static oil source fractures during the reservoir formation period described in the embodiment of the present application;

[0044] Figure 2 It is a structural block diagram of the static oil source fracture conductivity evaluation system during the reservoir formation period described in the embodiment of the present application;

[0045] Figure 3 This is a cross-sectional view of the oil source fault of survey line No. 5700 in the Y area of ​​the Xihu Sag in the embodiment of the present application;

[0046] Figure 4 This is a cross-sectional view of the oil source fault of survey line No. 5834 in the Y area of ​​the Xihu Sag in the embodiment of the present application;

[0047] Figure 5 This is a cross-sectional view of the oil source fault of the survey line No. 6000 in the Y area of ​​the Xihu Sag in the embodiment of the present application;

[0048] Figure 6 This is a cross-sectional view of the oil source fault of survey line No. 6100 in the Y area of ​​the Xihu Sag in the embodiment of the present application;

[0049] Figure 7 is a scatter plot of the correlation between the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate of the oil source fault in the embodiment of the present application;

[0050] Figure 8 This is a scatter plot of the correlation between the total width of the oil source fault-induced fracture zone and the fault distance in the embodiment of the present application.

[0051] In the figure: 1. Data acquisition module, 2. Oil source fault identification module, 3. Measurement device, 4. Fault distance calculation module, 5. Fault fracture zone identification module, 6. Correlation analysis module, 7. Width calculation module, 8. Evaluation module. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. Based on the embodiments provided in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0053] Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. In addition, it can also be understood that although the efforts made in this development process may be complicated and lengthy, for ordinary technicians in this field related to the content disclosed in this application, some changes in design, manufacturing or production based on the technical content disclosed in this application are just conventional technical means, and should not be understood as insufficient content disclosed in this application.

[0054] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application may be combined with other embodiments without conflict.

[0055] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantity limitation, and may indicate the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0056] The embodiment of the present application provides a method for evaluating the conductivity of static oil source faults during the reservoir formation period. Figure 1 Flow chart of the method for evaluating the conductivity of static oil source fractures during the reservoir formation period according to an embodiment of the present application. Figure 1 As shown, the process includes the following steps:

[0057] S1. Oil source fault identification steps: Determine the vertical cutting layer of the fault based on the existing seismic data results, and judge whether the fault is an oil source fault based on whether the fault cuts the underlying hydrocarbon source rock.

[0058] Specifically, the method for judging whether a fault is an oil source fault is based on whether the fault cuts the underlying source rock: if the fault cuts the underlying source rock, the fault is judged to be an oil source fault, and the fault serves as a channel for vertical transportation of natural gas; if the fault does not cut the underlying source rock, the fault is judged to be an invalid fault, and the fault does not have the ability to vertically transport natural gas.

[0059] S2. Fault throw calculation steps: Calculate the fault throw of each oil source fault based on the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line.

[0060] Specifically, the fault distance of each oil source fault is calculated according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line according to formula (1). Formula (1) is expressed as:

[0061] (1)

[0062] In the formula, is the break distance, is the vertical distance of the seismic section, is the horizontal distance of the seismic profile, is the angle between the fault strike and the survey line.

[0063] S3. Fault zone identification step: Calculate fault zone identification parameters based on resistivity and porosity logging parameters of the wells passing through the fault, and identify the upper and lower wall induced fracture zones based on the fault zone identification parameters.

[0064] Specifically, the fault zone identification parameters are calculated by formula (2), which is expressed as:

[0065] (2)

[0066] In the formula, Identify parameters for fault fracture zones; is the deep lateral resistivity, unit: ; is the shallow lateral resistivity, unit: ; is the acoustic porosity, unit: % is the density porosity, unit: % is the neutron porosity, unit: %.

[0067] In some embodiments, a specific method for identifying the induced fracture zones of the upper and lower plates according to the fault fracture zone identification parameters is as follows: if the fault fracture zone identification parameter curve is generally flat and similar to the upper and lower plate surrounding rock curves, it is identified as a sliding fracture zone; if the fault fracture zone identification parameter curve has a large overall variation range and is narrow and peak-shaped in many places, it is identified as an induced fracture zone; the induced fracture zone above the sliding fracture zone is the upper plate induced fracture zone, and the induced fracture zone below the sliding fracture zone is the lower plate induced fracture zone.

[0068] S4. Correlation analysis steps: Fit the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate to obtain the linear relationship between the widths of the induced fracture zones in the upper and lower plates; Fit the sum of the induced fracture zone widths and the fault distance to obtain the linear relationship between the sum of the induced fracture zone widths and the fault distance.

[0069] Specifically, the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate of the fault encountered by a single well are fitted, and the linear relationship between the widths of the induced fracture zones in the upper and lower plates is expressed as:

[0070] (3)

[0071] In the formula, is the width of the induced fracture zone in the hanging wall, is the width of the induced fracture zone in the footwall, is the correlation slope, is the correlation intercept.

[0072] Specifically, the sum of the widths of the induced fracture zones encountered by a single well is fitted with the fault throw, and the linear relationship between the sum of the widths of the induced fracture zones and the fault throw is expressed as:

[0073] (4)

[0074] In the formula, The total width of the induced crack zone, is the break distance, is the correlation slope, is the correlation intercept.

[0075] S5. Width calculation steps: According to the distribution characteristics of fault throw in the area where drilling has not yet begun, the widths of the upper and lower plates of the induced fracture zones are calculated according to the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones in the upper and lower plates, and the distribution characteristics of the widths of the upper and lower plates of the induced fracture zones are obtained.

[0076] S6. Evaluation steps: Evaluate the fault's ability to transport oil and gas based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates.

[0077] The above method in the embodiment of the present application describes the variation of the width of the induced fracture zone in the upper and lower plates of the oil source fault with the fault distance, and realizes the evaluation of the oil and gas transport capacity of the static oil source fault during the reservoir formation period.

[0078] It should be noted that the steps shown in the above process or the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0079] The present application also provides a static oil source fracture conductivity evaluation system during the reservoir formation period. Figure 2 : is a structural block diagram of a static oil source fracture conductivity evaluation system during the reservoir formation period according to an embodiment of the present application. The static oil source fracture conductivity evaluation system during the reservoir formation period includes:

[0080] Data acquisition module 1, used to obtain existing seismic data results;

[0081] The oil source fault identification module 2 is used to determine the vertical cutting layer of the fault according to the existing seismic data results, and to judge whether the fault is an oil source fault according to whether the fault cuts the underlying hydrocarbon source rock;

[0082] Measuring device 3, measuring the vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line;

[0083] The fault distance calculation module 4 calculates the fault distance of each oil source fault according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line;

[0084] Fault zone identification module 5, which calculates fault zone identification parameters according to resistivity and porosity logging parameters of the fault-passing well, and identifies the upper and lower plate induced fracture zones according to the fault zone identification parameters;

[0085] Correlation analysis module 6, fitting the width of the induced fracture zone of the upper plate and the width of the induced fracture zone of the lower plate to obtain the linear relationship between the widths of the induced fracture zones of the upper plate and the lower plate; fitting the sum of the widths of the induced fracture zones and the fault distance to obtain the linear relationship between the sum of the widths of the induced fracture zones and the fault distance;

[0086] The width calculation module 7 calculates the widths of the upper and lower plates of the induced fracture zone according to the distribution characteristics of the fault throw in the area where drilling has not yet begun, according to the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones of the upper and lower plates, and obtains the distribution characteristics of the widths of the induced fracture zones of the upper and lower plates;

[0087] Evaluation module 8 evaluates the fault's ability to transport oil and gas based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates.

[0088] Specifically, the measuring device may be an existing measuring device.

[0089] The above system of the embodiment of the present application describes the variation of the width of the induced fracture zone in the upper and lower plates of the oil source fault with the fault distance, and realizes the evaluation of the oil and gas transport capacity of the oil source fault that is static during the accumulation period.

[0090] The effectiveness of the above-mentioned method and system for evaluating the conductivity of static oil source faults during the reservoir formation period will be described below in conjunction with specific embodiments.

[0091] Example: Take the study of natural gas migration along faults in the Huagang Formation in the Y area of ​​the Xihu Sag as an example. The steps are:

[0092] S1. Identification of oil source faults

[0093] Using the seismic data of the Y area in the Xihu Sag and combining the configuration relationship between faults and the source rock series of the Pinghu Formation, a total of 16 major oil-source faults were identified (see Figures 3 to 6 ).

[0094] S2. Break distance calculation

[0095] Measure the vertical and horizontal distances of each oil source fault that disconnects the top surface of each stratum, as well as the angle between the fault strike and the survey line. , calculate the fault distance of each oil source fault, and the results are shown in Table 1.

[0096] Table 1

[0097]

[0098] S3. Fault zone identification

[0099] There are no wells in the Y area of ​​the Xihu Sag that have encountered fault planes. Therefore, wells in adjacent areas that have encountered fault planes were selected to identify the structural development characteristics of the fault zone based on their logging data. The results are shown in Table 2.

[0100] Table 2

[0101]

[0102] S4. Correlation analysis

[0103] By drawing a scatter plot of the correlation between the width of the induced fracture zone in the upper wall and the width of the induced fracture zone in the lower wall (see Figure 7 ), the linear relationship between the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate is fitted as follows:

[0104] (5)

[0105] By drawing a scatter plot of the correlation between the sum of the induced fracture zone width and the fault throw (see Figure 8 ), the linear relationship between the sum of the induced fracture zone width and the fault distance is fitted as follows:

[0106] (6)

[0107] S5. Width calculation

[0108] According to the calculation results of the fault throw of the oil source fault mentioned above, the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate are calculated using the linear relationship formula (5) between the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate, and the linear relationship formula (6) between the total width of the induced fracture zone and the fault throw. The results are shown in Table 3.

[0109] Table 3

[0110]

[0111] S6. Evaluation

[0112] According to the distribution characteristics of the induced fracture zone, the favorable oil and gas migration position is evaluated. As shown in Table 3, fault FY-4, fault FY-5, and fault FY-7 have stronger oil and gas transport capacity than other faults.

[0113] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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.

[0114] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for evaluating the conductivity of static oil source faults during the reservoir formation period, characterized in that: The following steps are involved: Oil source fault identification steps: determine the vertical cutting layer of the fault based on the existing seismic data results, and judge whether the fault is an oil source fault based on whether the fault cuts the underlying source rock; Fault throw calculation steps: Calculate the fault throw of each oil source fault according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line; Fault zone identification steps: Calculate fault zone identification parameters based on resistivity and porosity logging parameters of the wells passing through the fault, and identify the upper and lower wall induced fracture zones based on the fault zone identification parameters; Correlation analysis steps: fitting the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate to obtain the linear relationship between the widths of the induced fracture zones in the upper and lower plates; fitting the sum of the widths of the induced fracture zones and the fault distance to obtain the linear relationship between the sum of the widths of the induced fracture zones and the fault distance; Width calculation steps: according to the distribution characteristics of fault throw in the area where drilling has not yet begun, the widths of the upper and lower plates of the induced fracture zone are calculated according to the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones of the upper and lower plates, and the distribution characteristics of the widths of the upper and lower plates of the induced fracture zone are obtained; Evaluation steps: Based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates, the fault's ability to transport oil and gas is evaluated.

2. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 1, characterized in that: In the oil source fault identification step, the method for judging whether the fault is an oil source fault is based on whether the fault cuts the underlying source rock: if the fault cuts the underlying source rock, the fault is judged to be an oil source fault, and the fault serves as a channel for vertically transporting natural gas; if the fault does not cut the underlying source rock, the fault is judged to be an invalid fault, and the fault does not have the ability to vertically transport natural gas.

3. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 1, characterized in that: In the fault calculation step, the fault distance of each oil source fault is calculated according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line according to formula (1). Formula (1) is expressed as: （1） In the formula, is the break distance, is the vertical distance of the seismic section, is the horizontal distance of the seismic profile, is the angle between the fault strike and the survey line.

4. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 1, characterized in that: In the fault zone identification step, the fault zone identification parameters are calculated by formula (2), which is expressed as: （2） In the formula, Identify parameters for fault fracture zones; is the deep lateral resistivity, unit: ; is the shallow lateral resistivity, unit: ; is the acoustic porosity, unit: % is the density porosity, unit: % is the neutron porosity, unit: %.

5. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 1, characterized in that: In the fault and fracture zone identification step, the specific method for identifying the upper and lower plate induced fracture zones according to the fault and fracture zone identification parameters is as follows: if the fault and fracture zone identification parameter curve is overall gentle and similar to the upper and lower plate surrounding rock curves, it is identified as a sliding fracture zone; if the fault and fracture zone identification parameter curve has an overall large variation range and is narrow and peak-shaped in many places, it is identified as an induced fracture zone; the induced fracture zone above the sliding fracture zone is the upper plate induced fracture zone, and the induced fracture zone below the sliding fracture zone is the lower plate induced fracture zone.

6. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 1, characterized in that: In the correlation analysis step, the linear relationship between the widths of the induced crack zones of the upper and lower plates is expressed as: （3） In the formula, is the width of the induced fracture zone in the hanging wall, is the width of the induced fracture zone in the footwall, is the correlation slope, is the correlation intercept; The linear relationship between the sum of the induced crack widths and the fault throw is expressed as: （4） In the formula, The total width of the induced crack zone, is the break distance, is the correlation slope, is the correlation intercept.

7. The method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in claim 6, characterized in that: The total width of the induced fracture zone is equal to the width of the induced fracture zone in the upper plate plus the width of the induced fracture zone in the lower plate.

8. A system for evaluating the conductivity of static oil source fractures during the reservoir formation period, used to implement the method for evaluating the conductivity of static oil source fractures during the reservoir formation period as claimed in any one of claims 1 to 7, characterized in that: include: Data acquisition module, used to obtain existing seismic data results; The oil source fault identification module is used to determine the vertical cutting layer of the fault based on the existing seismic data results, and to judge whether the fault is an oil source fault based on whether the fault cuts the underlying hydrocarbon source rock; Measuring device, measuring the vertical distance and horizontal distance of each oil source fault seismic profile and the angle between the fault strike and the survey line; A fault distance calculation module calculates the fault distance of each oil source fault according to the measured vertical distance and horizontal distance of the seismic profile of each oil source fault and the angle between the fault strike and the survey line; The fault zone identification module calculates the fault zone identification parameters based on the resistivity and porosity logging parameters of the fault wells, and identifies the upper and lower plate induced fracture zones based on the fault zone identification parameters; The correlation analysis module fits the width of the induced fracture zone in the upper plate and the width of the induced fracture zone in the lower plate to obtain the linear relationship between the widths of the induced fracture zones in the upper and lower plates; fits the sum of the widths of the induced fracture zone and the fault distance to obtain the linear relationship between the sum of the widths of the induced fracture zone and the fault distance; The width calculation module calculates the width of the upper and lower plates of the induced fracture zone according to the distribution characteristics of the fault throw in the area where drilling has not yet begun, based on the linear relationship between the width of the induced fracture zone and the fault throw and the linear relationship between the widths of the induced fracture zones of the upper and lower plates, and obtains the distribution characteristics of the widths of the induced fracture zones of the upper and lower plates; The evaluation module evaluates the fault's ability to transport oil and gas based on the distribution characteristics of the width of the induced fracture zones in the upper and lower plates.

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