Three-dimensional earthquake fine interpretation and multi-attribute combined complex fracture system analysis method

Abstract

The invention relates to the frontier field of the geological exploration technology, and discloses a three-dimensional seismic fine interpretation and multi-attribute combined complex fracture system analysis method, which comprises the steps of S1, data acquisition and data preprocessing; s2, constructing a sequence stratigraphic framework; s3, three-dimensional seismic interpretation; s4, performing multi-attribute analysis; s5, carrying out geometric and kinematic analysis on the fracture system; s6, constructing a dynamic evolution mode; and S7, analyzing the influence of oil and gas accumulation. According to the method disclosed by the invention, the three-dimensional seismic data, the logging data and the sequence stratigraphic framework are comprehensively utilized, and a comprehensive fracture system analysis means is provided. Through multi-attribute analysis, the accuracy of fracture system identification and the meticulous degree of analysis are improved. A multi-stage dynamic evolution mode is constructed, the long-term evolution law of the fracture system and the deep influence of the fracture system on oil and gas accumulation are disclosed, the blank in the aspect of multi-stage dynamic evolution analysis of the stretching strike-slip fracture system in the prior art is filled, and scientific basis and technical support are provided for oil and gas exploration.

Description

Technical Field

[0001] The present disclosure relates to a frontier field of geological exploration technology, and specifically to a complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes. Background Art

[0002] Extensional strike-slip fault systems are widely present in various sedimentary basins, and their complex structural pattern profoundly affects the evolution of depressions and the formation of oil and gas traps. In the real geological background, extensional and strike-slip structures often coexist, forming a highly complex fault system, whose dynamic evolution process plays a vital role in the migration and accumulation of oil and gas. However, the existing technology is still insufficient in studying the multi-level dynamic evolution mechanism of such complex fault systems, and it is difficult to fully reveal their control over oil and gas accumulation. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention aims to provide a complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes.

[0004] To achieve the above objectives, the present disclosure adopts the following technical solutions:

[0005] A complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes includes the following steps:

[0006] S1. Data collection and data preprocessing

[0007] Collect 3D seismic data, well logging data and drilling records in the study area, and pre-process the 3D seismic data;

[0008] S2. Construction of sequence stratigraphic framework

[0009] Based on 3D seismic data and well logging data, sequence interfaces are identified, sequences at all levels are divided, and sequence stratigraphic framework is constructed;

[0010] S3. 3D Seismic Interpretation

[0011] Under the sequence stratigraphic framework, three-dimensional seismic interpretation is carried out to depict the geometric morphology, distribution characteristics and mutual relationship of the extensional strike-slip fault system, and to draw a planar distribution map of the fault system;

[0012] S4. Multi-attribute analysis

[0013] Based on 3D seismic interpretation and combined with multi-attribute information of seismic interface data, the plane distribution diagram of the fault system drawn is corrected to clarify the plane evolution characteristics of the extensional strike-slip fault system.

[0014] S5. Fracture system geometry and kinematics analysis

[0015] Analyze the geometrical and kinematic characteristics of extensional strike-slip fault systems;

[0016] S6. Dynamic Evolution Model Construction

[0017] Based on the analysis of geometric and kinematic characteristics, a multi-level dynamic evolution model of the extensional strike-slip fault system is constructed;

[0018] S7. Analysis of the impact of oil and gas accumulation

[0019] Combined with the dynamic evolution model, the control mechanism of the extensional strike-slip fault system on the oil and gas migration path, trap structure and oil and gas accumulation is analyzed.

[0020] In some embodiments of the present disclosure, data collection includes: utilizing gamma ray logging, natural potential logging, and sonic logging.

[0021] In some embodiments of the present disclosure, data preprocessing includes: denoising, amplitude balancing and speed analysis.

[0022] In some embodiments of the present disclosure, a sequence stratigraphic framework is constructed based on seismic reflection characteristics and well logging curves.

[0023] In some embodiments of the present disclosure, a detailed three-dimensional seismic interpretation is performed to accurately depict the geometric morphology, distribution characteristics and mutual relationships of the extensional strike-slip fault system and draw a planar layout map of the fault system.

[0024] In some embodiments of the present disclosure, 3D seismic interpretation includes delineating the branches, inter-fault relationships, and spatial distribution of extensional strike-slip fault systems within an established sequence stratigraphic framework.

[0025] In some embodiments of the present disclosure, the multi-attribute analysis includes: variance attribute analysis, ant body attribute analysis, inclination attribute analysis, and edge detection attribute analysis.

[0026] In some embodiments of the present disclosure, dynamic evolution model construction includes: visualizing the structure and stratigraphic heterogeneity of the study area based on the planar evolution characteristics of the extensional strike-slip fault system.

[0027] In some embodiments of the present disclosure, the oil and gas accumulation impact analysis includes migration path analysis, trap structure analysis, and reservoir and caprock analysis to clarify the role of the fracture system in the oil and gas accumulation process.

[0028] In some embodiments of the present disclosure, the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes also includes: using cases to verify the effectiveness of the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes, and predicting favorable areas for oil and gas exploration based on this.

[0029] Compared with the prior art, the complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes according to some embodiments of the present disclosure has beneficial technical effects. For example, the complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes according to some embodiments of the present disclosure comprehensively utilizes 3D seismic data, logging data and sequence stratigraphic framework, and provides a comprehensive means of fault system analysis. Through multi-attribute analysis, the accuracy of fault system identification and the level of detail of analysis are improved. A multi-level dynamic evolution model is constructed, revealing the long-term evolution law of the fault system and its profound impact on oil and gas accumulation. For another example, the complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes according to some embodiments of the present disclosure verifies the effectiveness of the method through specific case studies, providing scientific guidance and technical support for oil and gas exploration. For another example, the complex fault system analysis method combining three-dimensional seismic fine interpretation and multiple attributes in some embodiments of the present disclosure provides a systematic and comprehensive complex fault system analysis method combining three-dimensional seismic fine interpretation and multiple attributes, which deeply analyzes the geometric characteristics of the fault system and its dynamic evolution process through the fine three-dimensional seismic interpretation and multiple attributes under the stratigraphic framework, fills the gap in the prior art in the multi-level dynamic evolution analysis of extensional strike-slip fault systems, and also provides a scientific basis and technical support for oil and gas exploration, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0031] Figure 1 Shows an overview of the Bohai Bay Basin and its structural features in the study area. Figure 1 Center A shows the precise structural location of the focus study area in the Bohai Bay Basin. Figure 1 Figure B shows the details of the structural units of the Yellow River Mouth East Depression and the Miao South Depression, including key seismic survey lines and well location layout.

[0032] Figure 2 The sequence stratigraphic framework of the Yellow River Mouth East Sag and Miao Southwest Sag is shown.

[0033] Figure 3 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 Middle AA' seismic section, Figure 3 The original cross section is shown in a. Figure 3 Middle b shows the interpreted cross-section comparison.

[0034] Figure 4 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 Middle BB' seismic profile, Figure 4 The original cross section is shown in a. Figure 4 Middle b shows the interpreted cross section comparison (b).

[0035] Figure 5 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 CC' seismic profile, Figure 5 The original cross section is shown in a. Figure 5 Middle b shows the interpreted cross section comparison (b).

[0036] Figure 6 The interpreted seismic sections in the main line direction are shown. Figure 6 A shows the interpreted seismic section DD'. Figure 6 B shows the interpreted seismic profile EE′. Figure 6 The interpreted seismic profile FF′ is shown in C. Figure 6 D shows the interpreted seismic profile GG′. Figure 6 E shows the interpreted seismic profile HH'. Figure 6 F shows the interpreted seismic profile II′. Figure 6 G shows the interpreted seismic profile JJ' (see the locations of DD', EE', FF', GG', HH', II' Figure 1 Note: F1: Secondary fault No. 1 of the eastern branch of the Tanlu fault zone; F2: Secondary fault No. 2 of the eastern branch of the Tanlu fault zone.

[0037] Figure 7 The multi-attribute analysis of the T02 interface (the top surface of the lower section of the Neogene Minghuazhen Formation) is shown. Figure 7 a shows the variance property; Figure 7 The middle b shows the ant body attributes; Figure 7 In c, edge detection properties are shown; Figure 7 The inclination property is shown in (d).

[0038] Figure 8 The geometric morphology and spatial distribution of the main faults of T02 (top surface of the lower section of the Neogene Minghuazhen Formation) are shown.

[0039] Fig. 9 The multi-attribute analysis of the T5 interface (top surface of the third segment of the Shahejie Formation in the Paleogene) is shown. Fig. 9 a shows the variance property; Fig. 9 The middle b shows the ant body attributes; Fig. 9 In c, edge detection properties are shown; Fig. 9 The inclination property is shown in (d).

[0040] Fig.10 The main fault geometry and spatial distribution of T5 (top surface of the third segment of the Shahejie Formation in the Paleogene) are shown.

[0041] Fig.11The rose diagram of fault strike at each sequence interface in the study area is shown.

[0042] Fig.12 The diagram shows the planar distribution of the fault system and the overlay of the stratigraphic thickness map. Fig.12 A in the middle shows the plane distribution of the fault system at the T5 interface (the top surface of the third segment of the Shahejie Formation in the Paleogene) and the overlay of the equal thickness map of the third segment of the Shahejie Formation. Fig.12 Middle B shows the planar distribution of the fault system at the T3 interface (top surface of the Paleogene Shahejie Formation) and the overlay of the isopach maps of the first and second segments of the Shahejie Formation.

[0043] Fig.13 The relationship between strike-slip and extensional faults in the East Depression of the Yellow River Mouth and the Southwest Depression of Miaohe at different stages and the sub-depression type model are shown. Fig.13 Middle a shows the E2k deposition period, with concealed strike-slip. Fig.13 Middle b shows the E3s4 deposition period, segmented strike-slip faulting, and terminal extension. Fig.13 Middle c shows the E2s3 deposition period, with segmented penetration of the strike-slip fault and terminal extension. Fig.13 Figure d shows E3s 1-2 During the E3d deposition period, the strike-slip fault was penetrated as a whole. Fig.13 Figure e shows N1m L During the sedimentation period, there was a transition from concealed strike-slip faults to through-going strike-slip faults.

[0044] Fig.14 The trap distribution and fault system overlay analysis are shown. Fig.14 A in the figure shows the superposition of the trap distribution on the top surface of E3s1 and the planar distribution of the fault system. Fig.14 Figure B shows the superposition of the N1g top surface trap distribution and the fault system plane distribution.

[0045] Fig.15 The oil and gas accumulation pattern is shown. Fig.15 Figure a shows the extensional faults controlling the oil and gas accumulation pattern. Fig.15 Figure b shows the oil and gas accumulation pattern controlled by strike-slip faults. Fig.15 Middle (c) shows that extensional strike-slip faults control the oil and gas accumulation pattern. DETAILED DESCRIPTION

[0046] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0047] In some embodiments of the present disclosure, a complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes may include the following steps:

[0048] S1. Data collection and preprocessing

[0049] Collect 3D seismic data, well logging data and drilling records in the study area, and pre-process the 3D seismic data;

[0050] S2. Construction of sequence stratigraphic framework

[0051] Based on 3D seismic data and well logging data, sequence interfaces are identified, sequences at all levels are divided, and sequence stratigraphic framework is constructed;

[0052] S3. 3D Seismic Interpretation

[0053] Under the sequence stratigraphic framework, three-dimensional seismic interpretation is carried out to depict the geometric morphology and distribution characteristics of the extensional strike-slip fault system and draw a planar distribution map of the fault system;

[0054] S4. Multi-attribute analysis

[0055] Based on 3D seismic interpretation and combined with multi-attribute information of seismic interface data, the plane distribution diagram of the fault system drawn is corrected to clarify the plane evolution characteristics of the extensional strike-slip fault system.

[0056] S5. Fracture system geometry and kinematics analysis

[0057] Analyze the geometrical and kinematic characteristics of extensional strike-slip fault systems;

[0058] S6. Dynamic Evolution Model Construction

[0059] Based on the analysis of geometric and kinematic characteristics, a multi-level dynamic evolution model of the extensional strike-slip fault system is constructed;

[0060] S7. Analysis of the impact of oil and gas accumulation

[0061] Combined with the dynamic evolution model, the control mechanism of the extensional strike-slip fault system on the oil and gas migration path, the trap structure and the oil and gas accumulation is analyzed. In some embodiments of the present disclosure, data acquisition may include: using gamma ray logging (GR), natural potential logging (SP) and acoustic logging (AC).

[0062] In some embodiments, detailed data acquisition is performed on the target study area, including high-resolution 3D seismic data, detailed well logging information and drilling records.

[0063] In some embodiments of the present disclosure, data preprocessing may include: denoising, amplitude balancing, and speed analysis.

[0064] In some embodiments, data preprocessing may include: denoising, amplitude equalization and velocity analysis to improve data quality and lay the foundation for subsequent interpretation. In terms of logging data, a variety of technical means such as gamma ray logging (GR), natural potential logging (SP), and acoustic logging (AC) are used to comprehensively and accurately extract lithological characteristics and formation information.

[0065] In some embodiments of the present disclosure, a sequence stratigraphic framework is constructed based on seismic reflection characteristics and well logging curves.

[0066] In some embodiments, based on the principles of sequence stratigraphy, the seismic reflection characteristics and logging curves are deeply analyzed, the three-level sequences and their internal system domain interfaces are carefully divided, and a detailed and relatively accurate sequence stratigraphic model is constructed to provide a clear geological framework for subsequent three-dimensional seismic interpretation.

[0067] In some embodiments of the present disclosure, 3D seismic interpretation may include delineating the branches, inter-fault relationships, and spatial distribution of extensional strike-slip fault systems within an established sequence stratigraphic framework.

[0068] In some embodiments, key strata in the study area are analyzed one by one, the fault system is described in detail, and a planar distribution map of the fault system is preliminarily drawn based on this, providing an intuitive basis for subsequent analysis.

[0069] In some embodiments of the present disclosure, the multi-attribute analysis includes: variance attribute analysis, ant body attribute analysis, inclination attribute analysis, and edge detection attribute analysis.

[0070] In some embodiments, after completing the three-dimensional seismic interpretation, a comprehensive and detailed description of the fault system is performed by using a combination of diversified seismic attribute data such as variance attributes, ant tracking attributes, dip characteristics, and edge detection attributes. Specifically, the variance attribute, as a cornerstone, provides a solid foundation for the initial identification of faults; the ant tracking attribute, with its unique advantages, deeply captures and presents those subtle small fault details; the dip characteristics are used to correct and optimize the geometric shape of the fault to ensure its accuracy; finally, the edge detection attribute enhances the detailed description of the fault boundary, making the boundary of the fault system clearer and more identifiable. This series of multi-dimensional attribute information works together to achieve high-precision identification and in-depth analysis of the fault system.

[0071] In some embodiments of the present disclosure, geometric features may include, for example, strike, dip, and branching form. Kinematic features may include, for example, sliding direction and evolution process. By deeply analyzing the geometric and kinematic features of the fault system, its multi-level dynamic evolution law is revealed.

[0072] In some embodiments of the present disclosure, dynamic evolution model construction includes: visualizing the structure and stratigraphic heterogeneity of the study area based on the planar evolution characteristics of the extensional strike-slip fault system.

[0073] In some embodiments, based on the geometric characteristics of the fault system and the results of kinematic analysis, the tectonic equilibrium profile analysis method is used to construct a multi-level dynamic evolution model of the extensional strike-slip fault system to simulate the evolution trajectory of the extensional strike-slip fault system under different tectonic stress backgrounds, clearly showing its tectonic activities at various stages and its shaping effect on the tectonic pattern of the basin. The establishment of the multi-level dynamic evolution model deepens the understanding of the formation mechanism of the fault system and also provides an important tool for revealing its long-term evolution law.

[0074] In some embodiments of the present disclosure, the oil and gas accumulation impact analysis may include migration path analysis, trap structure analysis, and reservoir and caprock analysis to clarify the role of the fracture system in the oil and gas accumulation process.

[0075] In some embodiments, migration pathway analysis may include exploring how fracture systems serve as preferred pathways for oil and gas migration, affecting the direction and efficiency of oil and gas migration from source rocks to reservoirs.

[0076] In some embodiments, the trap structure analysis may include: analyzing how the fault system generates oil and gas traps, such as fault block traps, fault anticline traps, etc., through complex structural deformation, thereby providing favorable places for oil and gas accumulation.

[0077] Reservoir and cap rock analysis can include: combining the geological characteristics of the formation, comprehensively evaluating the impact of the extensional strike-slip fault system on the reservoir quality and cap rock sealing performance, and screening out high-quality oil and gas reservoirs and effective sealing layers.

[0078] According to the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes in some embodiments of the present disclosure, through comprehensive analysis, the dynamic evolution process of extensional strike-slip fault systems and their key role in the oil and gas accumulation process are fully revealed, providing a solid theoretical basis and guiding direction for scientific decision-making and practical operations in the field of oil and gas exploration.

[0079] In some embodiments of the present disclosure, the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes may also include: using cases to verify the effectiveness of the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes, and predicting favorable areas for oil and gas exploration based on this.

[0080] A specific implementation case is provided below to explain the present disclosure in detail.

[0081] Taking the Yellow River Mouth East Depression and the Miao Southwest Depression as the research areas, the complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination in some embodiments of the present disclosure was used to conduct actual case analysis. Figure 1 The Huanghekou East Depression and Miaoxinan Depression shown in A are located in the southern part of the Bohai Sea and are important oil and gas enrichment areas in the Bohai Bay Basin. Figure 1 As shown in B, the eastern branch of the strong strike-slip fault in the Laizhou Bay section of the Tanlu Fault passes through the study area from north to south in a "double track" shape. The Tanlu Fault Zone is a regional deep fault zone that runs through eastern China and has a long and complex history of activity. The right-lateral strike-slip of the Cenozoic Tanlu Fault Zone controls the evolution and tectonic features of the depression. The study area has developed structural units such as the North Sub-Depression, South Sub-Depression and East Sub-Depression of Miaoxinan Depression, as well as the East Sub-Depression of the Yellow River Mouth. The depression develops Paleogene to Neogene strata (including the Kongdian Formation, Shahejie Formation, Dongying Formation, Guantao Formation and Minghuazhen Formation).

[0082] In this embodiment, the complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes specifically includes the following steps:

[0083] S11. Data collection and data preprocessing

[0084] Collecting 3D seismic data, well logging data and drilling records in the Huanghekou East Depression and Miaoxinan Depression areas, and preprocessing the 3D seismic data;

[0085] S12. Precision construction of sequence stratigraphic framework

[0086] Using the acquired three-dimensional seismic and well logging data, a detailed sequence stratigraphic framework was constructed, such as Figure 2 By finely identifying sequence interfaces, dividing third-order sequences, and defining system tract interfaces, the stratigraphic evolution history of the study area from the Kongdian Formation to the Minghuazhen Formation was revealed, and the Cenozoic strata were subdivided into seven third-order sequences according to the depression evolution stage, laying a solid foundation for subsequent in-depth analysis.

[0087] S13. 3D seismic interpretation

[0088] In the framework of the sequence stratigraphic framework, a detailed 3D seismic interpretation was conducted to deeply analyze the vertical geometry, development characteristics and mutual relationship of the extensional strike-slip fault system. The extensional strike-slip faults in the study area have various shapes, including shovel-shaped, "Y"-shaped, reverse "Y"-shaped, multi-level "Y"-shaped and flower-shaped. The strike-slip faults develop continuously in the deep layer, and form complex negative flower-shaped or semi-flower-shaped structures near the surface, see Figure 3-Figure 6 , Figure 3 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 The middle AA' seismic section shows the vertical distribution characteristics of the extensional fault system. Figure 3The original cross section is shown in a. Figure 3 Middle b shows the interpreted cross-section comparison. Figure 4 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 The middle BB' seismic profile shows the vertical distribution characteristics of the extensional fault system. Figure 4 The original cross section is shown in a. Figure 4 Middle b shows the interpreted cross section comparison (b). Figure 5 The seismic section analysis shows the vertical distribution of the extensional fault system. Figure 1 The CC' seismic section shows the vertical distribution characteristics of the extensional fault system. Figure 5 The original cross section is shown in a. Figure 5 Middle b shows the interpreted cross section comparison (b). Figure 6 Interpreted seismic sections in the direction of the main survey line are shown, showing the vertical distribution of strike-slip and extensional strike-slip fault systems. Figure 6 A shows the interpreted seismic section DD'. Figure 6 B shows the interpreted seismic profile EE′. Figure 6 The interpreted seismic profile FF′ is shown in C. Figure 6 D shows the interpreted seismic profile GG'. Figure 6 E shows the interpreted seismic profile HH'. Figure 6 F shows the interpreted seismic profile II′. Figure 6 G shows the interpreted seismic profile JJ' (see the locations of DD', EE', FF', GG', HH', II' Figure 1 Note: F1: Secondary fault No. 1 of the eastern branch of the Tanlu fault zone; F2: Secondary fault No. 2 of the eastern branch of the Tanlu fault zone.

[0089] S14. Multi-attribute analysis

[0090] Based on the detailed interpretation of 3D seismic data, the multi-source seismic information such as variance attributes, ant body attributes, dip attributes and edge detection attributes are integrated to draw the plane distribution map of the extensional strike-slip fault system in each key layer. By analyzing these attributes item by item, see Figure 7-10 , Figure 7 The multi-attribute analysis of the T02 interface (the top surface of the lower section of the Neogene Minghuazhen Formation) is shown. Figure 7 a shows the variance property; Figure 7 The middle b shows the ant body attributes; Figure 7 In c, edge detection properties are shown; Figure 7 The inclination property is shown in (d). Figure 8 The geometric morphology and spatial distribution of the main faults of T02 (top surface of the lower section of the Neogene Minghuazhen Formation) are shown. Fig. 9 The multi-attribute analysis of the T5 interface (top surface of the third segment of the Shahejie Formation in the Paleogene) is shown. Fig. 9a shows the variance property; Fig. 9 The middle b shows the ant body attributes; Fig. 9 In c, edge detection properties are shown; Fig. 9 The inclination property is shown in (d). Fig.10 The geometric morphology and spatial distribution of the main faults in T5 (top surface of the third segment of the Shahejie Formation in the Paleogene) are shown, achieving a more comprehensive and accurate understanding of the fault system.

[0091] (1) Variance attribute analysis:

[0092] First, the variance attribute is calculated, which is a basic step in identifying discontinuities in seismic data. The variance attribute can help identify the initial fault plane distribution. The variance attribute is more sensitive to large faults such as primary and secondary faults (see Figure 7 b, Fig. 9 b).

[0093] (2) Ant body attribute extraction:

[0094] Based on the analysis of the development characteristics of primary and secondary faults by variance attributes, the ant body technique is used to identify the specific locations of small faults (third-level faults). Ant body attributes are very effective in capturing the direction and connectivity of faults (see Figure 7 a, Fig. 9 a).

[0095] (3) Application of inclination attribute:

[0096] By extracting the dip attribute, the dip change of the stratum can be analyzed, and the plane geometry and development trend of the fault can be further corrected ( Figure 7 d, 9d).

[0097] (4) Edge detection attribute usage:

[0098] Use edge detection properties to enhance the resolution of the fracture boundary. This step can clearly outline the fracture boundary and refine the planar development characteristics of the complex fracture system (see Figure 7 c, Fig. 9 c).

[0099] The results of all attributes are considered together to form a complete fault interpretation. The planar position and morphology of the fault can be verified and corrected by superimposing the results of different attributes (see Figure 8 , Fig.10 ).

[0100] S15. Geometry and kinematics analysis of fracture systems

[0101] In-depth analysis of the geometric and kinematic characteristics of the extensional strike-slip fault system reveals its multi-level dynamic evolution process. By drawing a rose diagram of the fault strike, see Fig.11 , Fig.11 The rose diagram of fault strike at each sequence interface in the study area shows that the fault strike gradually changes from multi-directional to concentrated in the NE-NEE direction, reflecting the complex changes in the tectonic stress field.

[0102] Combined with the characteristics of fault system development and its control on sequence development and depression evolution, see Fig.12 , Fig.12 The diagram shows the planar distribution of the fault system and the overlay of the stratigraphic thickness map. Fig.12 A in the middle shows the plane distribution of the fault system at the T5 interface (the top surface of the third segment of the Shahejie Formation in the Paleogene) and the overlay of the equal thickness map of the third segment of the Shahejie Formation. Fig.12 Figure B shows the plane distribution of the fault system at the T3 interface (top surface of the Paleogene Shahejie Formation) and the overlay of the isopach maps of the first and second segments of the Shahejie Formation, and a multi-level dynamic evolution model of the extensional strike-slip fault system is constructed. Fig.13 , Fig.13 The relationship between strike-slip and extensional faults in the East Depression of the Yellow River Mouth and the Southwest Depression of Miaohe at different stages and the sub-depression type model are shown. Fig.13 Middle a shows the E2k deposition period, with concealed strike-slip. Fig.13 Middle b shows the E3s4 deposition period, segmented strike-slip faulting, and terminal extension. Fig.13 Middle c shows the E2s3 deposition period, with segmented penetration of the strike-slip fault and terminal extension. Fig.13 Figure d shows E3s 1-2 During the E3d deposition period, the strike-slip fault was penetrated as a whole. Fig.13 Figure e shows N1m L During the sedimentation period, the hidden strike-slip faults transformed into penetrating strike-slip faults. This model reveals the evolutionary characteristics of the fault system under different tectonic stress fields and its profound impact on the basin structure and oil and gas accumulation.

[0103] S17. Analysis of the impact of oil and gas accumulation

[0104] Based on the dynamic evolution model of the fault system, the control mechanism of the fault system on the oil and gas migration path, trap structure and oil and gas accumulation is deeply discussed, and the favorable areas for oil and gas exploration are predicted accordingly. Fig.14 and Fig.15 , Fig.14 The trap distribution and fault system overlay analysis are shown. Fig.14 A in the middle shows the superposition of the trap distribution on the top surface of E3s1 and the plane distribution of the fault system, indicating the control of the fault system on the development of deep traps. Fig.14 Figure B shows the superposition of the distribution of traps on the top surface of N1g and the planar distribution of the fault system, indicating the control of the fault system on the development of deep traps. Fig.15 The oil and gas accumulation pattern is shown. Fig.15 Figure a shows the extensional faults controlling the oil and gas accumulation pattern. Fig.15Figure b shows the oil and gas accumulation pattern controlled by strike-slip faults. Fig.15 Middle (c) shows that extensional strike-slip faults control the oil and gas accumulation pattern.

[0105] S16. Dynamic Evolution Model Construction

[0106] The study proposed three oil and gas accumulation models: extensional fault-controlled accumulation, strike-slip fault-controlled accumulation and extensional strike-slip composite fault-controlled accumulation, which provide important references for future oil and gas exploration.

[0107] By using the methods of some embodiments of the present disclosure, the dynamic evolution process of the extensional strike-slip fault system in the East Yellow River Mouth Depression and the Southwest Miao Depression was successfully analyzed, and the key influence of the fault system on oil and gas accumulation was clarified, providing a scientific basis for oil and gas exploration in the region. The effectiveness and applicability of the disclosed method were verified through in-depth analysis of the case studies in the East Yellow River Mouth Depression and the Southwest Miao Depression.

[0108] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes, characterized in that: The following steps are involved: S1. Data collection and data preprocessing Collecting 3D seismic data, well logging data and drilling records in the study area, and preprocessing the 3D seismic data; S2. Construction of sequence stratigraphic framework Based on the three-dimensional seismic data and the well logging data, sequence interfaces are identified, sequences of various levels are divided, and a sequence stratigraphic framework is constructed; S3. 3D Seismic Interpretation Under the sequence stratigraphic framework, three-dimensional seismic interpretation is carried out to depict the geometric morphology, distribution characteristics and mutual relationship of the extensional strike-slip fault system, and to draw a planar distribution map of the fault system; S4. Multi-attribute analysis On the basis of 3D seismic interpretation, combined with the multi-attribute information of seismic interface data, the plane distribution diagram of the fault system drawn is corrected to clarify the plane evolution characteristics of the extensional strike-slip fault system; S5. Fracture system geometry and kinematics analysis Analyze the geometrical characteristics and kinematic characteristics of the extensional strike-slip fault system; S6. Dynamic Evolution Model Construction Based on the analysis of the geometric and kinematic characteristics, a multi-level dynamic evolution model of the extensional strike-slip fault system is constructed; S7. Analysis of the impact of oil and gas accumulation Combined with the dynamic evolution model, the control mechanism of the extensional strike-slip fault system on the oil and gas migration path, closure structure and oil and gas accumulation is analyzed.

2. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The data collection includes: utilizing gamma ray logging, natural potential logging and sonic logging.

3. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The data preprocessing includes: denoising, amplitude balancing and speed analysis.

4. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The sequence stratigraphic framework is constructed based on seismic reflection characteristics and well logging curves.

5. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: Carry out detailed three-dimensional seismic interpretation to accurately depict the geometric morphology, distribution characteristics and mutual relationships of the extensional strike-slip fault system, and draw a planar layout map of the fault system.

6. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The three-dimensional seismic interpretation includes: describing the branches, inter-fault relationships and spatial distribution of the extensional strike-slip fault system within the established sequence stratigraphic framework.

7. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The multi-attribute analysis includes: variance attribute analysis, ant body attribute analysis, inclination attribute analysis and edge detection attribute analysis.

8. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The dynamic evolution model construction includes: visualizing the structure and stratigraphic heterogeneity of the study area based on the planar evolution characteristics of the extensional strike-slip fault system.

9. The complex fault system analysis method combining 3D seismic fine interpretation and multi-attribute combination according to claim 1 is characterized in that: The analysis of the impact of oil and gas accumulation includes migration path analysis, trap structure analysis, and reservoir and cap rock analysis to clarify the role of the fault system in the oil and gas accumulation process.

10. The complex fault system analysis method combining 3D seismic fine interpretation with multiple attributes according to claim 1, characterized in that: It also includes: using cases to verify the effectiveness of the complex fault system analysis method combining three-dimensional seismic fine interpretation with multiple attributes, and predicting favorable areas for oil and gas exploration based on this.

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