Geological genesis-based present tectonic constraint low-permeability reservoir hierarchical classification evaluation method, device, equipment and medium

Abstract

The application discloses a kind of present tectonic constraint low-permeability reservoir grading classification evaluation method, device, equipment and medium based on geological genesis, comprising: carrying out low-permeability reservoir geological genesis analysis;Obtain the top and bottom interfaces of oil group or sub-oil group in time domain;Obtain the top interface depth domain structure of oil group or sub-oil group, namely present tectonic structure;According to the geological genesis of low-permeability reservoir and the top interface depth domain structure of oil group or sub-oil group, based on the relationship between porosity and permeability and depth on well, obtain the plane low-permeability reservoir grading classification information;Carry out seismic density, longitudinal wave velocity, transverse wave velocity three-parameter inversion to obtain seismic data volume;Carry out seismic distinguishable level low-permeability high-quality reservoir prediction;Carry out seismic indistinguishable level low-permeability relatively high-quality reservoir prediction;According to the prediction results of seismic distinguishable level low-permeability high-quality reservoir and seismic indistinguishable level low-permeability relatively high-quality reservoir, obtain low-permeability reservoir grading classification evaluation result.Therefore, the present application can realize offshore low-permeability high-quality reservoir fine characterization.

Description

Technical Field

[0001] This invention relates to the field of geological research technology for offshore oilfield development, specifically to a method, apparatus, equipment, and medium for classifying and evaluating current structurally constrained low-permeability reservoirs based on their geological origin. Background Technology

[0002] Predicting high-quality, low-permeability reservoirs in medium-deep formations is crucial for offshore oil and gas exploration and development. Due to their deep burial and the influence of diagenesis, these reservoirs exhibit poor physical properties and strong heterogeneity. The distribution of relatively high-permeability "sweet spots" within them is controlled by multiple factors, including sedimentary microfacies and diagenetic evolution, making the prediction of the spatial characteristics of high-quality reservoirs extremely challenging.

[0003] Traditional reservoir evaluation methods often focus on single-factor analysis using well logging data or seismic attributes, failing to effectively couple the fundamental geological causes controlling reservoir property differences with the alteration effects of subsequent tectonic evolution. Specifically, the properties of low-permeability reservoirs are controlled by geological factors such as sedimentary processes (e.g., sedimentary facies zones) and diagenesis (e.g., compaction, cementation, dissolution), which form the basic framework of reservoir properties. Current structural morphology (e.g., structural highs, slope zones, structural depressions) further exacerbates reservoir property differentiation by controlling diagenetic evolution paths (e.g., formation pressure, fluid activity). Furthermore, due to limitations in seismic resolution, it is difficult to achieve detailed characterization of high-quality low-permeability reservoirs below seismic resolution. Even based on constructing a sweet spot factor for low-permeability reservoirs, seismic inversion can only predict reservoirs with relatively good properties (e.g., permeability greater than 10 mD). Predicting relatively high-quality low-permeability reservoirs with permeability below 10 mD is extremely difficult, and these are often the reservoirs with larger reserves in oil fields.

[0004] Furthermore, unlike the dense well networks of onshore oilfields, offshore oilfields, due to high drilling costs and sparse well networks (well spacing was generally greater than 1000m in the early stages, and locally reached 200-500m in the later stages), have very limited directly obtained reservoir information. Limited well point data is insufficient to represent the complex lateral variations of the reservoir, resulting in significant uncertainty in inter-well predictions. Traditional methods, primarily based on well interpolation and extrapolation, suffer a sharp decline in accuracy when well control is insufficient, failing to meet the need for precise characterization of high-quality reservoir distribution. Therefore, it is necessary to fully utilize data from well logging, core analysis, thin sections, and 3D seismic data to establish a method for identifying low-permeability, high-quality reservoirs. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, in response to the above-mentioned problems, the purpose of the present invention is to provide a method, apparatus, equipment, and medium for the classification and evaluation of existing tectonically constrained low-permeability reservoirs based on geological genesis, which can fully utilize well logging, core, thin section, and 3D seismic data to conduct fine characterization of high-quality low-permeability offshore reservoirs.

[0006] To achieve the above-mentioned objectives, the technical solution adopted by this invention is as follows:

[0007] In a first aspect, the present invention provides a method for classifying and evaluating existing tectonically constrained low-permeability reservoirs based on their geological origin, comprising: Geological genesis analysis of low-permeability reservoirs was conducted using well logging, core samples, and thin sections. Using 3D seismic data, well-seismic combined tracking and interpretation are used to obtain the top and bottom interfaces of oil groups or sub-oil groups in the time domain; Based on the top interface of the oil group or sub-oil group in the time domain, the depth domain structure of the top interface of the oil group or sub-oil group is obtained based on the time-depth relationship of well-seismic calibration, which is the current structure. Based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, the classification information of planar low-permeability reservoirs is obtained based on the relationship between well porosity and permeability and depth. Using 3D seismic data and well logging, with the time domain top / bottom interface of oil group or sub-oil group as the time window constraint, the seismic data volume is obtained by inverting three parameters of seismic density, P-wave velocity and S-wave velocity. Based on the classification information of low-permeability reservoirs and seismic data, we will carry out the prediction of high-quality low-permeability reservoirs that can be distinguished by seismic levels. Based on the classification information of low-permeability reservoirs and seismic data, we will conduct prediction of relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data. Based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs, the final classification and evaluation results of low-permeability reservoirs are obtained.

[0008] Some possible implementations involve using well logging, core samples, and thin sections to conduct geological genetic analysis of low-permeability reservoirs, including: Based on core and thin section observations and descriptions, combined with well logging facies analysis, the sedimentary facies type of the target layer was identified; Based on thin sections of cast bodies, scanning electron microscopy, analysis of diagenetic minerals, and diagenetic evolution sequences, the diagenetic type of the target layer was identified; Based on the sedimentary facies type and diagenetic type of the target layer, the main geological factors controlling the differences in reservoir properties are determined.

[0009] Some possible implementations involve obtaining the current structure of the depth domain of the top interface of the oil group or sub-oil group based on the time-depth relationship of well-seismic calibration, according to the top interface of the oil group or sub-oil group in the time domain. This includes: Based on well seismic calibration, the time-depth relationship of each well is obtained, and the fitting formula of the time-depth relationship is obtained or the velocity field is constructed. The obtained oil group or sub-oil group time domain top interface is converted into a depth domain interface by using the time-depth relationship fitting formula or velocity field. Based on the deep domain interface, a deep domain interface construction diagram is created, forming the current construction diagram of the deep domain structure of the top interface of the oil group or sub-oil group.

[0010] In some possible implementations, based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil-bearing or sub-oil-bearing groups, planar classification information of low-permeability reservoirs is obtained based on the relationship between surface porosity and permeability and depth. The specific process is as follows: Collect porosity and permeability data of drilled oil or sub-oil groups, and create cross-plots of porosity, permeability and depth respectively; Based on the cross plot of porosity, permeability and depth, and combined with the analysis results of the main controlling factors of reservoir properties, vertical classification information of low-permeability reservoirs is obtained. Based on the vertical classification information of low-permeability reservoirs and combined with the current structural map, the classification information of planar low-permeability reservoirs is obtained.

[0011] Some possible implementations involve predicting seismically distinguishable levels of high-quality low-permeability reservoirs based on low-permeability reservoir classification information and seismic data, including: By statistically analyzing the porosity and permeability data of drilled oil groups or sub-oil groups, and combining them with the pore throat radius and drainage pressure, the reservoir classification information of oil groups or sub-oil groups is obtained, and the reservoirs are divided into reservoirs I, II, and III. Based on the reservoir classification information of oil group or sub-oil group, the P-wave impedance and S-wave impedance are calculated according to the P-wave velocity, S-wave velocity and density curves of actual drilled wells, and a fitting formula for the sweet spot factor of low-permeability reservoirs is constructed. Based on the fitting formula of the sweet spot factor of low-permeability reservoir, and according to the inversion results of three parameters of seismic density, P-wave velocity and S-wave velocity, the seismic data volume of low-permeability high-quality reservoir is obtained. Based on the seismic data volume of low-permeability high-quality reservoirs, the planar seismic attributes reflecting low-permeability high-quality reservoirs are extracted with the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints. Based on the planar seismic properties of low-permeability high-quality reservoirs, the planar distribution of low-permeability high-quality reservoirs with seismic distinguishability is obtained by using the proportion of high-quality reservoirs in actual drilled wells.

[0012] In some possible implementations, based on low-permeability reservoir classification information and seismic data, prediction of relatively high-quality low-permeability reservoirs of seismically indistinguishable levels is carried out. The specific process is as follows: Based on the inversion results of three parameters—seismic density, P-wave velocity, and S-wave velocity—seismic data volume reflecting the P-wave / S-wave velocity ratio of low-permeability reservoirs is obtained. Based on the P / S wave velocity ratio seismic data volume, the planar seismic properties of the low-permeability reservoirs are extracted using the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints. Based on the planar seismic properties of low-permeability reservoirs, the planar distribution of high-quality low-permeability reservoirs of seismically indistinguishable grade is obtained by using actual well sedimentary facies calibration. Based on the seismically distinguishable class of low-permeability high-quality reservoir planar distribution, the distribution boundary of seismically distinguishable class of low-permeability high-quality reservoir is obtained. Based on the planar distribution of seismically indistinguishable low-permeability high-quality reservoirs, and constrained by the boundary of seismically indistinguishable low-permeability high-quality reservoir distribution, seismically indistinguishable low-permeability high-quality reservoirs are removed to obtain the planar distribution of seismically indistinguishable low-permeability relative high-quality reservoirs.

[0013] In some possible implementations, the final classification and evaluation results of low-permeability reservoirs are obtained based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs. The specific process is as follows: Based on the planar distribution of seismically distinguishable low-permeability high-quality reservoirs, the boundaries of seismically distinguishable low-permeability high-quality reservoirs are obtained. Obtain the planar distribution of relatively high-quality low-permeability reservoirs of seismic indistinguishable level; obtain the boundary of relatively high-quality low-permeability reservoirs of seismic indistinguishable level. Based on the boundary of seismically distinguishable low-permeability high-quality reservoirs and the boundary of seismically indistinguishable low-permeability relatively high-quality reservoirs, the final classification and evaluation results of low-permeability reservoirs are obtained.

[0014] Secondly, the present invention also provides a classification and evaluation device for current tectonically constrained low-permeability reservoirs based on geological genesis, comprising: The first unit is configured to conduct geological genesis analysis of low-permeability reservoirs using well logging, core samples, and thin sections. The second unit is configured to use three-dimensional seismic data, combining well and seismic data to track and interpret the top and bottom interfaces of oil groups or sub-oil groups in the time domain. The third unit is configured to obtain the depth domain structure of the top interface of the oil group or sub-oil group based on the time-depth relationship of well-seismic calibration, i.e., the current structure. The fourth unit is configured to obtain planar classification information of low-permeability reservoirs based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, and based on the relationship between well porosity and permeability and depth. The fifth unit is configured to use 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, to carry out the inversion of three parameters of seismic density, P-wave velocity, and S-wave velocity to obtain the seismic data volume. The sixth unit is configured to conduct seismic-distinguished-level prediction of high-quality low-permeability reservoirs based on low-permeability reservoir classification information and seismic data. The seventh unit is configured to predict relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data, based on the classification information of low-permeability reservoirs and seismic data. Unit 8 is configured to obtain the final classification and evaluation results of low-permeability reservoirs based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs.

[0015] Thirdly, the present invention also provides an electronic device, comprising: at least one processor; and a memory communicatively connected to the processor; wherein the memory stores instructions executable by the processor, the instructions being executed by the processor to enable the processor to perform the method described thereon.

[0016] Fourthly, the present invention also provides a computer-readable storage medium for storing one or more programs, said one or more programs including computer instructions for causing a computer to perform the method.

[0017] This invention, by adopting the above technical solutions, has the following characteristics: By organically combining the "innate" geological factors (sedimentation, diagenesis) and "acquired" tectonic alteration factors that control reservoir properties, this invention establishes a graded and classified evaluation standard, realizing the understanding of the genesis and spatial prediction of the heterogeneity of low-permeability reservoirs. It has the following advantages: 1. Innovative evaluation approach: This invention breaks through the limitations of traditional single-factor evaluation, systematically analyzes the control mechanism of low-permeability reservoir property differences from the perspective of geological genesis and structural coupling, making the evaluation results more geologically significant and predictive.

[0018] 2. Strong guidance: The low-permeability high-quality reservoir classification prediction map finally generated by this invention can clearly show the spatial distribution of different types of reservoirs, providing a direct and reliable basis for development strategy formulation, development plan preparation, and optimization and adjustment of development well network deployment.

[0019] In summary, this invention can be widely applied to offshore oil and gas exploration and development. Attached Figure Description

[0020] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. In the drawings: Figure 1 This is a flowchart of the classification and evaluation technology for current tectonically constrained low-permeability reservoirs based on geological genesis, according to an embodiment of the present invention. Figure 2 This is a cross-plot of the geological genesis analysis of low-permeability reservoirs in an embodiment of the present invention; Figure 3 This is a well-connected seismic profile of the top and bottom interfaces of an oil group or sub-oil group based on three-dimensional seismic data tracing and interpretation, according to an embodiment of the present invention. Figure 4 This is a plan view of the depth domain construction of the top interface of the oil group or sub-oil group according to an embodiment of the present invention; Figure 5 This is a diagram showing the relationship between porosity, permeability, and burial depth in an embodiment of the present invention. Figure 6 This is a classification diagram of low-permeability reservoirs according to an embodiment of the present invention; Figure 7 This is a cross-plot of seismic-classifiable low-permeability high-quality reservoir factors and a typical seismic profile diagram, representing an embodiment of the present invention. Figure 8 This is a planar distribution map of seismically distinguishable low-permeability high-quality reservoirs according to an embodiment of the present invention. Figure 9 This is a planar distribution diagram of relatively high-quality low-permeability reservoirs of indistinguishable seismic grade according to an embodiment of the present invention. Figure 10 This is a planar distribution diagram of the classification and distribution of low-permeability high-quality reservoirs according to an embodiment of the present invention; Figure 11 This is a structural diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0021] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0022] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0023] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "above," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure.

[0024] This invention provides a method, apparatus, equipment, and medium for the classification and evaluation of low-permeability reservoirs constrained by current geological structures based on their geological origin. The methods include: conducting geological origin analysis of low-permeability reservoirs using well logging, core samples, and thin sections; using 3D seismic data for well-seismic combined tracking and interpretation to obtain the top and bottom interfaces of oil groups or sub-oil groups in the time domain; based on the top interface of the oil group or sub-oil group in the time domain, obtaining the current structure of the top interface in the depth domain (i.e., the current structure) based on the time-depth relationship between well-seismic calibration and the top interface in the depth domain of the low-permeability reservoir; and obtaining planar low-permeability reservoirs based on the geological origin of the low-permeability reservoir and the deep domain structure of the top interface of the oil group or sub-oil group, and based on the relationship between surface porosity and permeability and depth. The invention utilizes 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, to perform three-parameter inversion of seismic density, P-wave velocity, and S-wave velocity to obtain a seismic data volume. Based on the seismic classification information and the seismic data volume, it predicts seismically distinguishable levels of high-quality low-permeability reservoirs. It also predicts seismically indistinguishable levels of relatively high-quality low-permeability reservoirs. Finally, based on the prediction results of seismically distinguishable and indistinguishable levels of high-quality and relatively high-permeability low-permeability reservoirs, the invention obtains the final classification and evaluation results of low-permeability reservoirs. Therefore, this invention enables spatial prediction of the heterogeneity of low-permeability reservoirs, facilitates the refined characterization of high-quality low-permeability reservoirs, guides the deployment and optimization of development well networks, and provides important technical support for the efficient development and scheme adjustment of underground oil and gas reservoirs.

[0025] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0026] Example 1: The method for classifying and evaluating current tectonically constrained low-permeability reservoirs based on geological genesis provided in this example includes the following steps: S1. Utilize well logging, core samples, and thin sections to conduct geological genetic analysis of low-permeability reservoirs.

[0027] In this embodiment, well logging, core samples, and thin sections are used to conduct geological genetic analysis of low-permeability reservoirs. The specific process is as follows: S11. Based on core and thin section observations and descriptions, combined with well logging facies analysis, the sedimentary facies type of the target layer is determined; S12. Based on thin sections of cast bodies, scanning electron microscopy, and analysis of diagenetic minerals, the diagenetic type and diagenetic evolution sequence of the target layer are identified. Among them, the diagenetic types include compaction, cementation, or dissolution. S13, combined with S11 and S12, determines the main geological causes controlling the differences in reservoir properties.

[0028] S2. Using 3D seismic data, well-seismic combined tracking and interpretation are used to obtain the time domain top and bottom interfaces of the target layer (oil group or sub-oil group).

[0029] In this embodiment, an oil group is a combination of several oil layers with similar genesis and reservoir characteristics, separated by stable strata, and is the basic geological unit for dividing the oilfield development stratigraphy; a sub-oil group is a secondary geological unit further subdivided within an oil group, composed of adjacent single oil layers with similar physical properties, and is the core unit for block injection-production development and fine correlation.

[0030] S3. Based on the top interface of the oil group or sub-oil group in the time domain, obtain the depth domain structure (i.e., the current structure) of the top interface of the oil group or sub-oil group based on the well-seismic calibration time-depth relationship.

[0031] In this embodiment, the specific process of obtaining the top interface depth domain construction of the oil group or sub-oil group based on the well-seismic calibration time-depth relationship is as follows: S31. Based on well seismic calibration, obtain the time-depth relationship of each well, and obtain the fitting formula of the time-depth relationship or construct the velocity field. S32. Convert the obtained oil group or sub-oil group time domain top interface into a depth domain interface using the time-depth relationship formula or velocity field. S33. Based on the results of step S32, create a depth domain interface structure diagram to form the current structure diagram of the top interface depth domain of the oil group or sub-oil group.

[0032] S4. Based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, obtain classification information of low-permeability reservoirs based on the relationship between well porosity and permeability and depth.

[0033] In this embodiment, the specific process for obtaining the classification information of low-permeability reservoirs is as follows: S41. Collect data on porosity and permeability of drilled oil or sub-oil groups, and create cross-plots of porosity, permeability and depth respectively. S42. Based on the results of step S41 and combined with the analysis results of the main controlling factors of reservoir properties, obtain the vertical classification information of low-permeability reservoirs. S43. Based on the analysis results of step S42 and combined with the current structural map, obtain the classification information of low-permeability reservoirs in the plane.

[0034] S5. Using 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, carry out the inversion of three parameters: seismic density, P-wave velocity, and S-wave velocity.

[0035] S6. Based on the classification information of low-permeability reservoirs, conduct prediction of high-quality low-permeability reservoirs that can be distinguished by seismic levels.

[0036] In this embodiment, the prediction of seismically distinguishable low-permeability high-quality reservoirs includes: S61. Collect data on porosity and permeability of drilled oil groups or sub-oil groups to obtain reservoir classification information of oil groups or sub-oil groups. S62. Based on the analysis results of step S61, calculate the longitudinal wave impedance and transverse wave impedance according to the longitudinal wave velocity, transverse wave velocity and density curves of the actual drilled well, and construct the sweet spot factor for low-permeability reservoirs. S63. Based on the results of step S62, and according to the inversion results of the three parameters of seismic density, P-wave velocity, and S-wave velocity in step S5, obtain the seismic data volume of low-permeability high-quality reservoir. S64. Based on the results of step S63, extract the planar seismic properties of the high-quality, low-permeability reservoirs with the time domain top and bottom interfaces of the oil group or sub-oil group as constraints. S65. Based on the results of step S64, the proportion of high-quality reservoirs in actual drilling is used for calibration to obtain the planar distribution of seismically distinguishable low-permeability high-quality reservoirs.

[0037] S7. Based on the classification information of low-permeability reservoirs, conduct prediction of relatively high-quality low-permeability reservoirs that cannot be distinguished by earthquakes.

[0038] In this embodiment, the prediction of relatively high-quality low-permeability reservoirs that cannot be distinguished by earthquakes is carried out. The specific process is as follows: S71. Based on the inversion results of the three parameters of seismic density, P-wave velocity, and S-wave velocity, obtain the seismic data volume reflecting the P-wave / S-wave velocity ratio of low-permeability reservoirs. S72. Based on the results of step S71, extract the planar seismic properties of the reactive low-permeability reservoir using the top and bottom interfaces of the time domain of the oil group or sub-oil group as constraints. S73. Based on the results of step S72, use the actual well sedimentary facies for calibration to obtain the planar distribution of seismically indistinguishable low-permeability high-quality reservoirs. S74. Based on the results of step S72, obtain the distribution boundary of seismically distinguishable low-permeability high-quality reservoirs. S75. Based on the results of steps S73 and S64, obtain the planar distribution of seismically distinguishable low-permeability relatively high-quality reservoirs.

[0039] S8. Based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs, obtain the final classification and evaluation results of low-permeability reservoirs.

[0040] In this embodiment, the final classification and evaluation results of low-permeability reservoirs are obtained through the following process: S81. Based on the results of S64, obtain the boundary of seismically distinguishable low-permeability high-quality reservoirs. S82. Based on the results of S75, obtain the boundary of relatively high-quality reservoirs with low permeability that cannot be distinguished by earthquake. S83. Based on the boundary of seismically distinguishable low-permeability high-quality reservoirs and the boundary of seismically indistinguishable low-permeability relatively high-quality reservoirs, obtain the final classification and evaluation results of low-permeability reservoirs.

[0041] The following detailed embodiments illustrate the specific application of the present invention's method for classifying and evaluating geologically constrained low-permeability reservoirs based on geological origin.

[0042] like Figure 1 As shown in this embodiment, the method for classifying and evaluating geologically constrained low-permeability reservoirs based on their geological origin includes: S1. Utilize well logging, core samples, and thin sections to conduct geological genetic analysis of low-permeability reservoirs. The specific process is as follows: S11. Based on core and thin section observations and descriptions, combined with well logging facies analysis, the sedimentary facies type of the target layer is determined; In this embodiment, in petroleum geology and reservoir evaluation, core and thin section observation and description specifically refer to macroscopic and microscopic observation of cores using the naked eye and microscope to identify lithology, sedimentary characteristics, oil-bearing properties and microscopic pore structure, providing basic geological basis for reservoir evaluation, sedimentary facies research and reservoir description. The specific process is existing technology and will not be described in detail here.

[0043] S12. Based on cast thin sections (cast thin sections are microscopic sections made by injecting dyed resin into the pores of rock samples and then grinding them, used for intuitive and quantitative observation and analysis of reservoir pore structure), scanning electron microscopy, and diagenetic mineral analysis, cross plots of permeability versus mudstone, felsic and cement content, and permeability versus grain size were prepared to clarify the diagenetic type (compaction, cementation, dissolution) and diagenetic evolution sequence of the target layer.

[0044] In this embodiment, through core observation, thin section identification, and mineral replacement relationship analysis, it was determined that the target layer mainly developed three types of diagenesis: compaction, cementation, and dissolution. Combined with the burial-geothermal evolution history, the diagenetic evolution sequence was reconstructed, and the control mechanism of various diagenetic processes on reservoir porosity formation and evolution was clarified, providing a geological basis for the prediction of high-quality reservoirs.

[0045] S13, combined with S11 and S12, determines the main geological causes controlling the differences in reservoir properties.

[0046] In this embodiment, by combining the research results of sedimentary facies and diagenesis, and using methods such as single-factor comparison and cross plot analysis, the influence intensity and contribution of sedimentation and diagenesis on reservoir properties are clarified, and the main geological causes controlling the differences in reservoir properties are finally determined.

[0047] like Figure 2 As shown, permeability is negatively correlated with clay content and cement content, and positively correlated with felsic content and particle size. Thin section analysis indicates that the target layer has a compaction rate of 60.9%-90% and a cementation rate of 1.4%-15.9%, indicating strong compaction and weak cementation. Furthermore, compaction reduces porosity by 24.4%-36.0% of the original porosity, while cementation reduces porosity by 0.6%-6.4% of the original porosity. Compaction has a more significant impact on physical properties. Therefore, in this example, compaction is the main cause of low permeability in the reservoir; this is just one example, and the study is not limited to this.

[0048] S2, such as Figure 3 As shown, by using three-dimensional seismic data and combining well and seismic data, the time domain top and bottom interfaces of the target layer (oil group or sub-oil group) are obtained through tracking and interpretation.

[0049] S3. Based on the well-seismic calibration time-depth relationship, obtain the current structure of the top interface depth domain of the oil group or sub-oil group, which is the current structure. The specific process is as follows: S31. Based on well seismic calibration, obtain the time-depth relationship of each well, and obtain the fitting formula of the time-depth relationship or construct the velocity field. S32. The obtained oil group or sub-oil group time domain top interface is converted into a depth domain interface using the established time-depth relationship or velocity field. The depth domain interface refers to the depth domain construction interface. S33. Based on the depth domain interface, create a depth domain interface construction diagram to form the current construction diagram of the top interface of the oil group or sub-oil group.

[0050] In this embodiment, based on the depth domain interface data, a Kriging interpolation meshing algorithm is used to perform spatial interpolation calculations on the depth of the target layer interface, forming depth domain interface mesh data, and then displaying it on a plane to form a depth domain interface construction map. For example... Figure 4 As shown, the current structure of the oil group's top surface is characterized by a high southwest and low northeast, with the structural depth gradually increasing towards the north and east, and the fault orientation is mainly near east-west and northeast-southwest.

[0051] S4. Obtain classification information for low-permeability reservoirs. The specific process is as follows: S41. Collect data on porosity and permeability of drilled oil or sub-oil groups, and create cross-plots of porosity, permeability and depth respectively. S42. Based on the results of S41 and combined with the analysis results of the main controlling factors of reservoir properties, obtain the vertical classification information of low-permeability reservoirs.

[0052] In this embodiment, based on the values ​​of porosity and permeability, the reservoir is vertically divided into: a weakly compacted high-porosity, high-permeability zone (porosity 10-25%, permeability 10-1000 mD, burial depth 1000-2500 m); a medium-compacted, medium-porosity, medium-permeability zone (porosity 5-23%, permeability 0.5-100 mD, burial depth 2500-2750 m); a relatively strongly compacted low-porosity, low-permeability zone (porosity 2-22%, permeability 0.1-10 mD, burial depth 2750-3250 m); and a strongly compacted ultra-low-porosity, ultra-low-permeability zone (porosity 1-15%, permeability 0.1-6 mD, burial depth 3250-4000 m).

[0053] S43. Based on the vertical classification information of low-permeability reservoirs and combined with the current structural map, obtain the horizontal classification information of low-permeability reservoirs.

[0054] In this embodiment, based on the depth range corresponding to the S42 reservoir zone and the current structural map, different colors are displayed for different depth ranges corresponding to the reservoir zone, thereby obtaining planar low-permeability reservoir classification information.

[0055] like Figure 5 As shown, porosity and permeability are negatively correlated with burial depth, meaning that as the burial depth gradually increases, porosity and permeability gradually decrease. like Figure 6 As shown, based on the relationship between porosity, permeability, and burial depth, and combined with the current structure of the oil-bearing formation's top surface, the reservoir exhibits vertical zonation and planar partitioning characteristics. Specifically, the reservoir can be divided into weakly compacted high-porosity, high-permeability zones; moderately compacted medium-porosity, medium-permeability zones; relatively strongly compacted low-porosity, low-permeability zones; and strongly compacted ultra-low-porosity, low-permeability zones. The specific classification method is as follows: based on the values ​​of porosity and permeability, the reservoir is vertically divided into weakly compacted high-porosity, high-permeability zones, corresponding to porosities of 10–25% and permeabilities of 10–1000 mD. The burial depth is 1000~2500m; medium compaction medium porosity medium permeability zone, corresponding to a porosity of 5~23% and a permeability of 0.5~100mD, burial depth 2500~2750m; relatively strong compaction low porosity low permeability zone, corresponding to a porosity of 2~22% and a permeability of 0.1~10mD, burial depth 2750~3250m; strong compaction ultra-low porosity ultra-low permeability zone, corresponding to a porosity of 1~15% and a permeability of 0.1~6mD, burial depth 3250~4000m.

[0056] S5. Using 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, carry out the inversion of three parameters: seismic density, P-wave velocity, and S-wave velocity.

[0057] S6. Conduct earthquake-detectable classification of low-permeability, high-quality reservoirs. The specific process is as follows: S61. Statistically analyze the porosity and permeability data of drilled oil or sub-oil groups, and combine them with data such as pore throat radius and displacement pressure to obtain reservoir classification information, and divide the reservoir into I, II and III. In this embodiment, reservoir types are classified according to the magnitude of each parameter. For example, a Class I reservoir is defined as having a porosity greater than 15%, a permeability greater than 50 mD, an average pore throat radius greater than 4 μm, and a displacement pressure less than 0.05 MPa. This is just one example, and the classification is not limited to this.

[0058] S62. Based on the reservoir segmentation results in step S61, calculate the P-wave impedance and S-wave impedance according to the actual drilled well's P-wave velocity, S-wave velocity, and density curves, and construct a fitting formula for the sweet spot factor of low-permeability reservoirs, i.e., the fitting formula for the sweet spot factor (sweet) is -0.0606. AI-0.9982 SI+5747795.63, where AI is the longitudinal wave impedance and SI is the transverse wave impedance; S63. Based on the fitting formula of the sweet spot factor of low-permeability reservoir, and according to the inversion results of the three parameters of seismic density, P-wave velocity and S-wave velocity, the seismic data volume of low-permeability high-quality reservoir is obtained. In this embodiment, based on the three-parameter inversion data, the longitudinal wave impedance (AI) and transverse wave impedance (SI) are calculated, and the reservoir sweet spot factor fitting formula (sweet) = -0.0606 is applied. AI-0.9982 The seismic data volume of low-permeability high-quality reservoirs calculated using the formula SI+5747795.63 is the sweet spot factor of low-permeability reservoirs.

[0059] S64. Based on the seismic data volume of low-permeability high-quality reservoirs, extract the planar seismic attributes reflecting the low-permeability high-quality reservoirs using the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints.

[0060] In this embodiment, based on the seismic data volume of low-permeability high-quality reservoirs, the maximum amplitude is extracted as the planar seismic attribute reflecting the low-permeability high-quality reservoirs, using the top and bottom interfaces of the oil group or sub-oil group as time windows.

[0061] S65. Based on planar seismic attributes, calibration is performed using the proportion of high-quality reservoirs in actual drilled wells (the statistical results of the proportion of high-quality reservoirs in the well are displayed on the extracted planar seismic attributes; the larger the proportion of high-quality reservoirs in the well, the larger the maximum amplitude attribute value). That is, the proportion of Type-I reservoirs in actual drilled wells is statistically analyzed, and then a threshold value for planar seismic attributes (greater than 0.5) is set to obtain the seismically distinguishable level of low-permeability high-quality reservoirs, i.e., the planar distribution of Type-I reservoirs.

[0062] In this embodiment, the proportion of Type-I reservoirs in actual drilled wells is statistically analyzed: single-well interpretation is carried out according to the S61 reservoir classification standard, and the proportion of Type-I reservoir thickness in each oil group or sub-oil group is statistically analyzed to determine the overall reservoir thickness. Type-I reservoirs are defined as reservoirs with porosity greater than 15%, permeability greater than 50 mD, average pore throat radius greater than 4 μm, and displacement pressure less than 0.05 MPa.

[0063] like Figure 7 As shown, constructing a sweet spot factor (sweet) for low-permeability reservoirs can effectively separate Type-I from Type-II and Type-III reservoirs. Combining the three-parameter inversion results of seismic density, P-wave velocity, and S-wave velocity, a seismic data volume reflecting high-quality low-permeability reservoirs can be obtained. Specifically, Type-I is separated from Type-II and Type-III reservoirs by a sweet spot value greater than this value, while Type-II / Type-III reservoirs have values ​​less than this value. Type-I is determined based on parameters such as porosity, permeability, pore throat radius, and displacement pressure, and varies for each oilfield. Based on the three-parameter inversion data, the P-wave impedance (AI) and S-wave impedance (SI) are calculated, and the reservoir sweet spot factor (sweet) = -0.0606 is applied. AI-0.9982 The seismic data volume of low-permeability high-quality reservoirs was obtained by calculating using the formula SI+5747795.63.

[0064] like Figure 8 As shown, Type-I reservoirs are mainly located in the current structural high areas in the south, with shallow burial depth and a small distribution range.

[0065] S7. Conduct prediction of relatively high-quality low-permeability reservoirs whose class cannot be distinguished by earthquakes. The specific process is as follows: S71. Based on the inversion results of the three parameters of seismic density, P-wave velocity, and S-wave velocity, obtain the seismic data volume reflecting the P-wave / S-wave velocity ratio of low-permeability reservoirs; the specific process is as follows: based on the three-parameter inversion data, directly calculate the P-wave velocity and S-wave velocity ratio to obtain the P-wave / S-wave velocity ratio seismic data volume.

[0066] S72. Based on the results of step S71, extract the planar seismic attributes of the low-permeability reservoir using the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints. The planar seismic attributes of the low-permeability reservoir refer to the sensitive seismic attributes that reflect the planar distribution of the low-permeability reservoir. Here, it refers to the minimum amplitude seismic attribute. The extraction method is as follows: based on the seismic data volume of the low-permeability high-quality reservoir, with the top and bottom interfaces of the oil group or sub-oil group in the time domain as time windows, extract the minimum amplitude as the planar seismic attribute of the low-permeability reservoir.

[0067] S73. Based on the results of step S72, calibration is performed using actual drilled sedimentary facies (the well sedimentary facies results are displayed on the extracted planar seismic attributes, and the seismic attribute characteristics corresponding to each sediment are analyzed. For example, the main channel corresponds to a low value area of ​​minimum amplitude seismic attribute, the inter-channel corresponds to a high value area of ​​minimum amplitude seismic attribute, and the minimum amplitude seismic attribute value corresponding to the channel edge is in between the two, thus determining the boundaries of different sedimentary facies zones). Seismic attribute threshold values ​​are set to obtain the boundaries of different sedimentary facies zones, thereby obtaining the planar distribution of seismically indistinguishable low-permeability high-quality reservoirs. For example, seismic attribute values ​​less than 1.75 represent the main channel, seismic attribute values ​​between (1.75, 1.80) represent the channel edge, and seismic attribute values ​​greater than 1.8 represent the inter-channel. Among them, the main channel and the channel edge are reservoirs II and III, respectively, while the inter-channel is mainly composed of mudstone deposits and is not a reservoir.

[0068] S74. Based on the results of step S6, obtain the distribution boundary of seismically distinguishable low-permeability high-quality reservoirs. In this embodiment, based on the seismic distinguishable level of low-permeability high-quality reservoir, i.e., the plane seismic attribute threshold value (greater than 0.5) corresponding to Type-Ⅰ reservoir, seismic attributes with values ​​less than the threshold value are deleted, and the boundary of the remaining seismic attributes is extracted as the boundary of the distribution of seismically distinguishable level of low-permeability high-quality reservoir.

[0069] S75. Based on the results of step S73, and using the boundary of step S74 as a constraint, remove the seismically distinguishable low-permeability high-quality reservoirs to obtain the planar distribution of seismically indistinguishable low-permeability relative high-quality reservoirs.

[0070] like Figure 9 As shown, the relatively high-quality low-permeability reservoirs that cannot be distinguished by earthquake levels are mainly located in areas far from the source, primarily in the main body and edges of river channels.

[0071] S8. Obtain the final classification and evaluation results of low-permeability reservoirs. The specific process is as follows: S81. Based on the results of step S64, obtain the boundary of the seismically distinguishable low-permeability high-quality reservoir. S82. Based on the results of step S75, obtain the boundary of the relatively high-quality reservoir with low permeability that cannot be distinguished by earthquake. S83. Based on the boundary of low-permeability high-quality reservoirs that can be distinguished by earthquakes and the boundary of low-permeability relatively high-quality reservoirs that cannot be distinguished by earthquakes, the two types of boundaries are superimposed and filled with different colors to obtain the final classification and evaluation results of low-permeability reservoirs.

[0072] In this embodiment, the final classification and evaluation result of low-permeability reservoirs refers to dividing low-permeability reservoirs into three categories: Category I reservoirs - low-permeability high-quality reservoirs with a proportion of more than 50% of Category I reservoirs in the well; Category II reservoirs - low-permeability high-quality reservoirs with a proportion of less than 50% of Category I reservoirs in the well, mainly consisting of riverbed deposits; and Category III reservoirs - secondary low-permeability high-quality reservoirs with a proportion of less than 50% of Category I reservoirs in the well, mainly consisting of riverbed deposits.

[0073] like Figure 10 It can be seen that Type I reservoirs are mainly located in the current structural high areas in the south, with shallow structural burial depth; Type II reservoirs are mainly located in areas far from the source, mainly in the main river channel, with deeper structural burial depth; and Type III reservoirs are mainly located in areas far from the source, mainly in the edge of the main river channel, with the deepest structural burial depth among the three types of reservoirs.

[0074] Based on the aforementioned cross-plot of porosity, permeability, and depth, the following structures are identified: shallow burial depth (1000-2500 m) corresponds to a porosity of 10-25% and a permeability of 10-1000 mD; deeper burial depths (2500-2750 m and 2750-3250 m) correspond to a medium-solidity, medium-porosity, and medium-permeability zone, respectively, and a strongly compacted, low-porosity, low-permeability zone, respectively, with corresponding porosities of 5-23% and 2-22% and permeabilities of 0.5-100 mD and 0.1-10 mD; and the deepest burial depth (3250-4000 m) corresponds to a porosity of 1-15% and a permeability of 0.1-6 mD.

[0075] Example 2: Following the method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological origin provided in Example 1, this example provides a device for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological origin. The device provided in this example can implement the method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological origin described in Example 1. This device can be implemented through software, hardware, or a combination of both. For ease of description, this example is described by dividing the functions into various units. Of course, in implementation, the functions of each unit can be implemented in one or more software and / or hardware components. For example, the device may include integrated or separate functional modules or units to perform the corresponding steps in the methods of Example 1. Since the device in this example is basically similar to the method example, the description process of this example is relatively simple. Relevant details can be found in the description of Example 1. The example of the device for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological origin provided by this invention is merely illustrative.

[0076] Specifically, this embodiment provides a classification and evaluation device for current tectonically constrained low-permeability reservoirs based on geological origin, comprising: The first unit is configured to conduct geological genesis analysis of low-permeability reservoirs using well logging, core samples, and thin sections. The second unit is configured to use three-dimensional seismic data, combining well and seismic data to track and interpret the top and bottom interfaces of oil groups or sub-oil groups in the time domain. The third unit is configured to obtain the depth domain structure of the top interface of the oil group or sub-oil group based on the time-depth relationship of well-seismic calibration, i.e., the current structure. The fourth unit is configured to obtain planar classification information of low-permeability reservoirs based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, and based on the relationship between well porosity and permeability and depth. The fifth unit is configured to use 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, to carry out the inversion of three parameters of seismic density, P-wave velocity, and S-wave velocity to obtain the seismic data volume. The sixth unit is configured to conduct seismic-distinguished-level prediction of high-quality low-permeability reservoirs based on low-permeability reservoir classification information and seismic data. The seventh unit is configured to predict relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data, based on the classification information of low-permeability reservoirs and seismic data. Unit 8 is configured to obtain the final classification and evaluation results of low-permeability reservoirs based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs.

[0077] Example 3: This example provides an electronic device corresponding to the geologically constrained low-permeability reservoir classification and evaluation method based on geological genesis provided in Example 1. The electronic device can be a client-side electronic device, such as a mobile phone, laptop, tablet, desktop computer, etc., to execute the method of Example 1.

[0078] like Figure 11 As shown, the electronic device includes a processor, a memory, a communication interface, and a bus. The processor, memory, and communication interface are connected via the bus to enable communication between them. The memory stores a computer program that can run on the processor. When the processor runs the computer program, it executes the method of Embodiment 1. The implementation principle and technical effects are similar to those of Embodiment 1, and will not be repeated here. Those skilled in the art will understand that... Figure 11 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computing device on which the present application is applied. The specific computing device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0079] In a preferred embodiment, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), and optical discs.

[0080] In a preferred embodiment, the processor can be any type of general-purpose processor such as a central processing unit (CPU) or a digital signal processor (DSP), and is not limited thereto.

[0081] Example 4: This example provides a computer-readable storage medium for storing one or more programs, the one or more programs including computer instructions, which, when executed by a computer, cause the computer to perform the method provided in Example 1 above.

[0082] In a preferred embodiment, the computer-readable storage medium may be a tangible device for holding and storing instructions executable, such as, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof. The computer-readable storage medium stores computer program instructions that cause a computer to perform the method provided in Embodiment 1 above.

[0083] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (devices), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0084] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0085] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0086] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In the description of this specification, the terms "a preferred embodiment," "furthermore," "specifically," "in this embodiment," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments in this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for grading and classifying low-permeability reservoirs based on geological genesis, characterized in that, include: Geological genesis analysis of low-permeability reservoirs was conducted using well logging, core samples, and thin sections. Using 3D seismic data, well-seismic combined tracking and interpretation are used to obtain the top and bottom interfaces of oil groups or sub-oil groups in the time domain; Based on the top interface of the oil group or sub-oil group in the time domain, the depth domain structure of the top interface of the oil group or sub-oil group is obtained based on the time-depth relationship of well-seismic calibration, which is the current structure. Based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, the classification information of planar low-permeability reservoirs is obtained based on the relationship between well porosity and permeability and depth. Using 3D seismic data and well logging, with the time domain top / bottom interface of oil group or sub-oil group as the time window constraint, the seismic data volume is obtained by inverting three parameters of seismic density, P-wave velocity and S-wave velocity. Based on the classification information of low-permeability reservoirs and seismic data, we will carry out the prediction of high-quality low-permeability reservoirs that can be distinguished by seismic levels. Based on the classification information of low-permeability reservoirs and seismic data, we will conduct prediction of relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data. Based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs, the final classification and evaluation results of low-permeability reservoirs are obtained.

2. The method for classifying and evaluating current tectonically constrained low-permeability reservoirs based on geological genesis as described in claim 1, characterized in that, Geological genesis analysis of low-permeability reservoirs was conducted using well logging, core samples, and thin sections, including: Based on core and thin section observations and descriptions, combined with well logging facies analysis, the sedimentary facies type of the target layer was identified; Based on thin sections of cast bodies, scanning electron microscopy, analysis of diagenetic minerals, and diagenetic evolution sequences, the diagenetic type of the target layer was identified; Based on the sedimentary facies type and diagenetic type of the target layer, the main geological factors controlling the differences in reservoir properties are determined.

3. The method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological genesis as described in claim 1, characterized in that, Based on the time domain top interface of the oil group or sub-oil group, the depth domain structure of the top interface of the oil group or sub-oil group, i.e., the current structure, is obtained based on the well-seismic calibration time-depth relationship, including: Based on well seismic calibration, the time-depth relationship of each well is obtained, and the fitting formula of the time-depth relationship is obtained or the velocity field is constructed. The obtained oil group or sub-oil group time domain top interface is converted into a depth domain interface by using the time-depth relationship fitting formula or velocity field. Based on the deep domain interface, a deep domain interface construction diagram is created, forming the current construction diagram of the deep domain structure of the top interface of the oil group or sub-oil group.

4. The method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological genesis as described in claim 1, characterized in that, Based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil-bearing or sub-oil-bearing groups, and based on the relationship between well porosity and permeability and depth, planar classification information of low-permeability reservoirs is obtained. The specific process is as follows: Collect porosity and permeability data of drilled oil or sub-oil groups, and create cross-plots of porosity, permeability and depth respectively; Based on the cross plot of porosity, permeability and depth, and combined with the analysis results of the main controlling factors of reservoir properties, vertical classification information of low-permeability reservoirs is obtained. Based on the vertical classification information of low-permeability reservoirs and combined with the current structural map, the classification information of planar low-permeability reservoirs is obtained.

5. The method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological genesis as described in claim 1, characterized in that, Based on the classification information of low-permeability reservoirs and seismic data, prediction of seismically distinguishable low-permeability high-quality reservoirs is carried out, including: By statistically analyzing the porosity and permeability data of drilled oil groups or sub-oil groups, and combining them with the pore throat radius and drainage pressure, the reservoir classification information of oil groups or sub-oil groups is obtained, and the reservoirs are divided into reservoirs I, II, and III. Based on the reservoir classification information of oil group or sub-oil group, the P-wave impedance and S-wave impedance are calculated according to the P-wave velocity, S-wave velocity and density curves of actual drilled wells, and a fitting formula for the sweet spot factor of low-permeability reservoirs is constructed. Based on the fitting formula of the sweet spot factor of low-permeability reservoir, and according to the inversion results of three parameters of seismic density, P-wave velocity and S-wave velocity, the seismic data volume of low-permeability high-quality reservoir is obtained. Based on the seismic data volume of low-permeability high-quality reservoirs, the planar seismic attributes reflecting low-permeability high-quality reservoirs are extracted with the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints. Based on the planar seismic properties of low-permeability high-quality reservoirs, the planar distribution of low-permeability high-quality reservoirs with seismic distinguishability is obtained by using the proportion of high-quality reservoirs in actual drilled wells.

6. The method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological origin as described in claim 5, characterized in that, Based on the classification information of low-permeability reservoirs and seismic data, prediction of relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data is carried out. The specific process is as follows: Based on the inversion results of three parameters—seismic density, P-wave velocity, and S-wave velocity—seismic data volume reflecting the P-wave / S-wave velocity ratio of low-permeability reservoirs is obtained. Based on the P / S wave velocity ratio seismic data volume, the planar seismic properties of the reactive low-permeability reservoir are extracted using the top and bottom interfaces of the oil group or sub-oil group in the time domain as constraints. Based on the planar seismic properties of low-permeability reservoirs, the planar distribution of high-quality low-permeability reservoirs of seismically indistinguishable grade is obtained by using actual well sedimentary facies calibration. Based on the seismically distinguishable class of low-permeability high-quality reservoir planar distribution, the distribution boundary of seismically distinguishable class of low-permeability high-quality reservoir is obtained. Based on the planar distribution of seismically indistinguishable low-permeability high-quality reservoirs, and constrained by the boundary of seismically indistinguishable low-permeability high-quality reservoir distribution, seismically indistinguishable low-permeability high-quality reservoirs are removed to obtain the planar distribution of seismically indistinguishable low-permeability relative high-quality reservoirs.

7. The method for classifying and evaluating tectonically constrained low-permeability reservoirs based on geological genesis as described in claim 1, characterized in that, Based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs, the final classification and evaluation results of low-permeability reservoirs are obtained. The specific process is as follows: Based on the planar distribution of seismically distinguishable low-permeability high-quality reservoirs, the boundaries of seismically distinguishable low-permeability high-quality reservoirs are obtained. Obtain the planar distribution of relatively high-quality low-permeability reservoirs of seismic indistinguishable level; obtain the boundary of relatively high-quality low-permeability reservoirs of seismic indistinguishable level. Based on the boundary of seismically distinguishable low-permeability high-quality reservoirs and the boundary of seismically indistinguishable low-permeability relatively high-quality reservoirs, the final classification and evaluation results of low-permeability reservoirs are obtained.

8. A classification and evaluation device for current tectonically constrained low-permeability reservoirs based on geological origin, comprising: The first unit is configured to conduct geological genesis analysis of low-permeability reservoirs using well logging, core samples, and thin sections. The second unit is configured to use three-dimensional seismic data, combining well and seismic data to track and interpret the top and bottom interfaces of oil groups or sub-oil groups in the time domain. The third unit is configured to obtain the depth domain structure of the top interface of the oil group or sub-oil group based on the time-depth relationship of well-seismic calibration, i.e., the current structure. The fourth unit is configured to obtain planar classification information of low-permeability reservoirs based on the geological genesis of low-permeability reservoirs and the top interface depth domain structure of oil groups or sub-oil groups, and based on the relationship between well porosity and permeability and depth. The fifth unit is configured to use 3D seismic data and well logging, with the top / bottom interface of the oil group or sub-oil group as the time window constraint, to carry out the inversion of three parameters of seismic density, P-wave velocity, and S-wave velocity to obtain the seismic data volume. The sixth unit is configured to conduct seismic-distinguished-level prediction of high-quality low-permeability reservoirs based on low-permeability reservoir classification information and seismic data. The seventh unit is configured to predict relatively high-quality low-permeability reservoirs that cannot be distinguished by seismic data, based on the classification information of low-permeability reservoirs and seismic data. Unit 8 is configured to obtain the final classification and evaluation results of low-permeability reservoirs based on the prediction results of seismically distinguishable low-permeability high-quality reservoirs and seismically indistinguishable low-permeability relatively high-quality reservoirs.

9. An electronic device, characterized in that, include: At least one processor; And a memory communicatively connected to the processor; wherein the memory stores instructions executable by the processor, the instructions being executed by the processor to enable the processor to perform the method according to any one of claims 1-7.

10. A computer-readable storage medium for storing one or more programs, characterized in that, The one or more programs include computer instructions for causing a computer to perform the method according to any one of claims 1-7.

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