Reservoir remaining oil saturation inversion method based on dynamic monitoring data

Abstract

The invention provides an oil reservoir remaining oil saturation inversion method based on dynamic monitoring data. The method comprises the steps of 1, collecting geological data; 2, establishing a three-dimensional fine geological model; step 3, correcting the three-dimensional fine geological model; 4, defining a fluid potential field by combining an oil-gas migration channel and a migration rule, and obtaining the distribution characteristics of remaining oil; and 5, predicting and comparing actual data to obtain the monitoring frequency of the dynamic monitoring well. According to the reservoir remaining oil saturation inversion method based on the dynamic monitoring data, guidance suggestions are provided for remaining oil development and dynamic monitoring frequency; and meanwhile, the corresponding three-dimensional geological model is specifically constructed by combining the existing geological data and development data of different oil and gas fields, so that the quantification of the remaining oil is realized, the operability is high, and the method is easy to popularize in different blocks and even different oil and gas fields.

Description

Technical Field

[0001] The present invention relates to the technical field of oilfield development, and particularly to a method for characterizing the distribution law of remaining oil in oil and gas reservoirs. Background Art

[0002] Through years of development, dynamic monitoring technology has gradually formed technologies in aspects such as basic experiments, monitoring plan design, monitoring data collection, data interpretation, and comprehensive application, becoming another important means to understand and evaluate the development dynamics and effects of oil reservoirs in addition to reservoir engineering and reservoir numerical simulation. The traditional reservoir engineering method based on the analytical solution of the seepage mechanics equation needs to greatly simplify the reservoir model and cannot fully consider the influence of reservoir heterogeneity and complex flow mechanisms. Reservoir numerical simulation is a conventional method for reservoir dynamic analysis and prediction. Its advantages are that the correlation between parameters based on mechanisms is clear, the method is mature after years of development and can be implemented based on commercial software. Its main limitation is that it depends on an accurate geological model and seepage mechanism, has a large error for blocks with unclear geological models or seepage mechanisms, and can only consider part of the monitoring data.

[0003] In the prior art, the considered factors are relatively single, such as gravity or migration channels, etc., and in the process of characterization, targeted data needs to be combined for processing, and corresponding analysis and prediction results are obtained according to the processing results. Due to its pertinence, it is difficult to directly apply it to different blocks or oil and gas fields. There is also a lack of a method with a correction function and easy to be widely applied.

[0004] In the Chinese patent application with the application number: CN201710882860.6, it relates to a method for predicting the remaining oil distribution in high-water-cut reservoirs of waterflooded oil reservoirs, belonging to the technical field of oilfield development. The present invention first determines the characteristic parameters required for characterizing the remaining oil distribution according to the oil reservoir geological research data, then establishes a migration model of oil and gas in the high-water-cut reservoir of the oil reservoir according to the determined characteristic parameters; finally, determines the amount of oil and gas accumulated in the trap during the shutdown period of the oil well according to the established migration model. This invention fully considers the action of gravity, can accurately predict the remaining oil distribution in the high-water-cut reservoir of the waterflooded oil reservoir, can effectively analyze and evaluate the formation process and enrichment location of the remaining oil in the watered-out layer under the action of gravity, guide the redigging of the remaining oil in the watered-out layer, and further improve the oil recovery rate of the oil reservoir. However, in reality, the distribution of remaining oil is not only controlled by a single factor, but is redistributed under the combined action of multiple factors, and due to the heterogeneity of the bottom layer, its distribution is also very uneven. Therefore, analyzing it as a large block in the same way may have differences in different blocks.

[0005] In the Chinese patent application with the application number: CN202011030748.8, a method and device for predicting remaining oil are involved. The method includes: creating a geological map for each development layer series in a preset work area, where the geological map includes a stratigraphic structure map, an isopach map of the oil layer, and a sedimentary microfacies map; performing superposition processing on the geological maps of multiple development layer series to obtain a comprehensive geological map; taking the oil wells and water wells in the preset work area as objects, and marking the actual production data of the preset work area on the comprehensive geological map; marking on the comprehensive geological map according to the water cut of the oil wells in the preset work area to form a water-flooded map; converting the water cut of the oil wells into the oil saturation of the oil wells, and converting the water-flooded map into a two-dimensional remaining oil distribution map according to the oil saturation of the oil wells; using the two-dimensional remaining oil distribution map to predict the remaining oil in the preset work area. The invention can intuitively predict the remaining oil in the preset work area by using the two-dimensional remaining oil distribution map, and the accuracy of the remaining oil distribution prediction is relatively high. However, the distance between oil wells in actual oilfield blocks is relatively large, and there is a large error in inversely calculating the remaining oil saturation between wells with a large distance based on the water cuts of oil wells and water wells.

[0006] In the Chinese patent application with the application number: CN201711343786.7, a method for quantitatively analyzing the remaining oil distribution law is involved. The method for quantitatively analyzing the remaining oil distribution law includes: Step 1, establishing a numerical simulation model, performing production history matching, and solving the model; Step 2, extracting result data and statistically analyzing each index parameter; Step 3, drawing frequency distribution maps of remaining oil saturation with structure, permeability, oil layer thickness, and pressure, and analyzing; Step 4, drawing frequency distribution maps and cumulative frequency distribution maps of remaining reserve abundance with structure, permeability, oil layer thickness, and pressure, and analyzing; Step 5, drawing frequency distribution maps and cumulative frequency distribution maps of recoverable reserve abundance with structure, permeability, oil layer thickness, and pressure, and analyzing; Step 6, comprehensively analyzing to obtain the result. The method for quantitatively analyzing the remaining oil distribution law is highly practical, analyzes the remaining oil distribution pattern and characteristics of the oilfield, and provides a basis for subsequent potential tapping and production increase. This patent obtains the remaining oil distribution pattern by analyzing the frequency distribution of each parameter. If the frequency change is not significant, the remaining oil characteristics cannot be accurately displayed, and the remaining oil saturation change cannot be inversely updated in real time according to the actual change data.

[0007] The above prior arts are all quite different from the present invention and fail to solve the technical problems we want to solve. Therefore, we have invented a method for characterizing the remaining oil distribution law of oil and gas reservoirs. Summary of the Invention

[0008] The object of the present invention is to provide a method for characterizing the remaining oil distribution law of oil and gas reservoirs, which conducts historical matching research on the basis of a numerical simulation model, clarifies the remaining oil distribution law, divides flow units according to dynamic understanding and the numerical simulation model, and analyzes the remaining oil potential tapping potential.

[0009] The object of the present invention can be achieved by the following technical measures: A method for inverting the remaining oil saturation in a reservoir based on dynamic monitoring data, the method for inverting the remaining oil saturation in a reservoir based on dynamic monitoring data comprising:

[0010] Step 1, collect geological data;

[0011] Step 2, establish a three-dimensional fine geological model;

[0012] Step 3, modify the three-dimensional fine geological model;

[0013] Step 4, delineate the fluid potential field in combination with the oil and gas migration channels and migration laws, and obtain the distribution characteristics of the remaining oil;

[0014] Step 5, predict and compare with actual data to obtain the monitoring frequency of the dynamic monitoring wells.

[0015] The object of the present invention can also be achieved by the following technical measures:

[0016] In Step 1, collect existing structure, stratigraphy, sedimentation, and physical property data to determine the characteristic parameters required to characterize the remaining oil distribution, and determine the corresponding constraint conditions according to the phase within the characteristic parameters.

[0017] In Step 1, re-interpret the faults based on seismic coherence attributes, re-identify the faults in the study area, generate the top structure map of the oil group through time-depth conversion of the velocity field and stratigraphic calibration of the actual drilled wells, and generate the top structure of each rhythm section inside the oil group with this as the constraint.

[0018] In Step 1, adopt the method of high-resolution sequence stratigraphy, with the principles of cycle correlation, hierarchical control, well-seismic combination, and multi-dimensional interaction as the stratification guiding principles, based on the principles of regional marker beds, auxiliary marker beds, curve morphological characteristics, and formation thickness changes, conduct fine stratigraphic correlation of the oil group, establish the isochronous stratigraphic framework of each small layer inside the oil group in the study area, and clarify the lithology, thickness, distribution characteristics, and their variation laws of the strata and oil layers.

[0019] In Step 1, on the basis of isochronous stratigraphic division and correlation, comprehensively analyze the coring wells in combination with the regional geological background, determine the sedimentary microfacies types of the sand bodies through vertical sequence analysis, single index facies analysis, and sedimentary cycle analysis, and then establish a typical sedimentary microfacies columnar diagram; then, based on well log facies analysis, establish the response relationship between the sedimentary microfacies and well log curves, divide the sedimentary microfacies in the whole area, and study the distribution characteristics and combination relationships of the sedimentary microfacies, and finally establish the sedimentary pattern of this area.

[0020] In Step 1, through systematic analysis of core observation and description, thin section identification, scanning electron microscopy, mercury injection capillary pressure curves, and logging data, study the microscopic characteristics and heterogeneity characteristics of the reservoir in the plane and profile; study the planar distribution characteristics of diagenetic facies to deepen the understanding of the reservoir.

[0021] In Step 1, conduct research on rock types and interstitial content, clarify the petrological characteristics of the reservoir, and compile a planar distribution map of microscopic mineral components.

[0022] Conduct research on reservoir diagenesis, analyze the types of diagenesis and their effects on reservoir physical properties, and compile a planar distribution map of diagenetic facies.

[0023] Conduct research on reservoir pore structure, pore type, and connectivity; conduct research on the distribution characteristics and heterogeneity of reservoir physical properties, compile a planar distribution map, and formulate reservoir classification criteria and comprehensive evaluation.

[0024] In Step 2, based on characteristic parameters and constraints, using logging data as the basis and combining well test data, correct the property parameters such as porosity, permeability, and saturation of each well point to establish a three-dimensional fine geological model that can fully reflect the structural characteristics, sand body distribution characteristics, and physical property distribution characteristics of the well area.

[0025] In Step 2, the model includes a structural and bedding model, a deterministic sedimentary microfacies model, a reservoir lithofacies model constrained by sedimentary microfacies, and porosity, permeability, and saturation models controlled by sedimentary microfacies.

[0026] In Step 3, dynamically correct the three-dimensional fine geological model in combination with actual dynamic monitoring data, and based on the aforementioned constraints, slice and partition the three-dimensional fine geological model. In a single slice partition, establish an oil and gas migration channel according to the lithofacies characteristics of the single slice partition.

[0027] In Step 4, in the dynamically corrected three-dimensional fine geological model, combine the oil and gas migration channels and migration laws to delineate the fluid potential field, so as to accurately obtain the distribution characteristics of remaining oil.

[0028] In Step 4, based on the established geological model, conduct reserve calculation; in the process of reserve calculation, according to the calculation principle of taking small layers as the unit vertically and sand bodies as the unit horizontally, apply parameters such as porosity, net-to-gross ratio, and oil-gas-water interface to calculate the original geological reserves in the model.

[0029] In Step 5, conduct a prediction for the second year based on the corrected model, and compare the prediction results with the actual results of the second year to guide the monitoring frequency of dynamic monitoring wells.

[0030] In step 5, guide the monitoring frequency of dynamic monitoring wells: import the first batch of monitoring data into the constraint model, and make a prediction of the remaining oil in the second year. Compare the prediction results with the second batch of monitoring data. If the difference is large, increase the monitoring intensity and predict the distribution of remaining oil in the third year. Compare the second batch of monitoring data. If the difference is not large, then the number of wells in the second batch of monitoring plan is considered to be the critical optimal number of wells.

[0031] The present invention is based on the re-understanding of the geological characteristics of the reservoir, combined with the existing geological data including strata, sedimentation, structure, physical properties, etc., based on well logging data, combined with the correction of parameter points such as well test data, to establish a three-dimensional fine geological model that can fully understand the structural characteristics, sand body distribution characteristics and physical property distribution characteristics of the well area, and conduct in-depth research on the abundance and distribution law of the remaining oil under the constraints of the three-dimensional fine geological model, so as to quantify the recoverable reserves of each type of remaining oil and gas, clarify the potential tapping objects and goals in the later stage, and optimize the dynamic monitoring frequency of monitoring wells.

[0032] The present invention can directly use existing geological data and development data to build models, and make corrections based on real-time development data. At the same time, the present invention also has strong transplantation capabilities. The research provided in the invention can be promoted in existing oil and gas fields, and the corresponding three-dimensional geological model can be specifically constructed by combining the existing geological data and development data of different oil and gas fields, so as to realize the quantification of residual oil. It has strong operability and is easy to promote in different blocks and even different oil and gas fields, so as to provide guidance and suggestions for the development of residual oil. Brief Description of the Figures

[0033] Figure 1 It is a flowchart of a specific embodiment of the method for inverting the remaining oil saturation of a reservoir based on dynamic monitoring data of the present invention;

[0034] Figure 2 A schematic diagram of formulating a dynamic monitoring scheme for the reservoir remaining oil saturation inversion method based on dynamic monitoring data of the present invention. Specific implementation method

[0035] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by ordinary technicians in the technical field to which the present invention belongs.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, and / or combinations thereof.

[0037] The method for inverting the remaining oil saturation in a reservoir based on dynamic monitoring data of the present invention includes:

[0038] Step 1, collect geological data;

[0039] Step 2, based on characteristic parameters and constraint conditions, taking well logging data as the basis, and combining data such as well testing to correct the pore, permeability, saturation and other property parameters of each well point, and establish a three-dimensional fine geological model that can fully reflect the structural characteristics, sand body distribution characteristics and physical property distribution characteristics of the well area.

[0040] Step 3, dynamically correct the three-dimensional fine geological model in combination with actual dynamic monitoring data, and slice and partition the three-dimensional fine geological model based on the foregoing constraint conditions, and establish an oil and gas migration channel for a single slice partition according to the lithofacies characteristics within the single slice partition.

[0041] Step 4, in the dynamically corrected three-dimensional fine geological model, delineate the fluid potential field in combination with the oil and gas migration channel and the migration law, so as to accurately obtain the distribution characteristics of the remaining oil.

[0042] Step 5, perform the prediction for the second year based on the corrected model, and compare with the actual data after the prediction. Import the first batch of monitoring data into the constraint model and perform the prediction of the remaining oil for the second year. Compare the prediction results with the second batch of monitoring data. If the difference is large, increase the monitoring intensity. At the same time, predict the distribution of the remaining oil for the third year and compare with the second batch of monitoring data. If the difference is small, then the number of wells in the second batch of monitoring schemes is considered to be the critical optimal number of wells.

[0043] The following are several specific embodiments of applying the present invention

[0044] Embodiment 1

[0045] In a specific embodiment 1 of applying the present invention, as Figure 1 shown, the method for inverting the remaining oil saturation in a reservoir based on dynamic monitoring data of the present invention specifically includes:

[0046] Step 1, collect geological data; determine the characteristic parameters required to characterize the remaining oil distribution based on the existing structural, stratigraphic, sedimentary and physical property data, and determine the corresponding constraint conditions according to the lithofacies within the characteristic parameters.

[0047] Based on seismic coherence attributes, fracture reinterpretation is carried out to re-identify faults in the study area. Through the time-depth conversion of the velocity field and the correction of the actual drilled well stratification, the top structure map of the oil formation is generated, and based on this constraint, the top structure of each rhythm section inside the oil formation is generated.

[0048] Using the method of high-resolution sequence stratigraphy, with the guiding principle of "cyclic correlation, hierarchical control, well-seismic combination, and multi-dimensional interaction" for stratification, based on the principles of regional marker beds, auxiliary marker beds, curve morphological characteristics, and formation thickness changes, fine stratigraphic correlation of the oil formation is carried out, an isochronous stratigraphic framework of each small layer inside the oil formation in the study area is established, and the lithology, thickness, distribution characteristics, and their variation laws of the formation and oil layers are clarified.

[0049] On the basis of isochronous stratigraphic division and correlation, combined with the regional geological background, core wells are analyzed in detail. By means of vertical sequence analysis, single-index facies analysis, sedimentary cycle analysis, etc., the sedimentary microfacies types of sand bodies are determined, and then a typical sedimentary microfacies columnar diagram is established. Then, based on well logging facies analysis, the response relationship between sedimentary microfacies and well logging curves is established, the sedimentary microfacies of the whole area are divided, and through the study of the distribution characteristics and combination relationships of sedimentary microfacies, the sedimentary model of this area is finally established.

[0050] By systematically analyzing data such as core observation and description, thin section identification, scanning electron microscopy, mercury injection capillary pressure curves, and well logging, the microscopic characteristics and heterogeneity characteristics of the reservoir in the plane and profile are studied. The plane distribution characteristics of diagenetic facies are studied to deepen the understanding of the reservoir.

[0051] Carry out research on rock types, interstitial content, etc., clarify the petrological characteristics of the reservoir, and compile a plane distribution map of microscopic mineral components.

[0052] Carry out research on reservoir diagenesis, analyze the types of diagenesis and their influence on reservoir physical properties, and compile a plane distribution map of diagenetic facies.

[0053] Carry out research on reservoir pore structure, pore type, and connectivity; carry out research on the distribution characteristics and heterogeneity of reservoir physical properties, compile a plane distribution map, formulate a reservoir classification standard and comprehensive evaluation.

[0054] Step 2: Based on characteristic parameters and constraint conditions, taking well logging data as the basis, combined with data such as well testing, the pore, permeability, saturation and other attribute parameters of each well point are corrected, and a three-dimensional fine geological model that can fully reflect the structural characteristics, sand body distribution characteristics, and physical property distribution characteristics of this well area is established;

[0055] The model includes a structure and bedding model, a deterministic sedimentary microfacies model, a reservoir lithofacies model constrained by sedimentary microfacies, and a porosity, permeability, and saturation model controlled by sedimentary microfacies.

[0056] Step 3: Dynamically correct the 3D fine geological model in combination with actual dynamic monitoring data. Based on the aforementioned constraints, partition the 3D fine geological model into slices. Within a single slice partition, establish an oil and gas migration channel according to the lithofacies characteristics.

[0057] Step 4: In the dynamically corrected 3D fine geological model, delineate the fluid potential field in combination with the oil and gas migration channels and migration laws, so as to accurately obtain the distribution characteristics of remaining oil.

[0058] Based on the established geological model, perform reserve calculation. During the reserve calculation process, according to the calculation principle of taking small layers as units vertically and sand bodies as units horizontally, apply parameters such as porosity, net-to-gross ratio, oil-gas-water interface, etc., to calculate the original geological reserves in the model.

[0059] Embodiment 2

[0060] In a specific Embodiment 2 of applying the present invention, as Figure 2 shown, the guidance on the monitoring frequency of dynamic monitoring wells by the reservoir remaining oil saturation inversion method based on dynamic monitoring data of the present invention specifically includes:

[0061] Step 1: Perform the prediction for the second year based on the corrected model, and compare the prediction result with the actual result of the second year, so as to guide the monitoring frequency of dynamic monitoring wells.

[0062] Predict the model and compare with the actual data after prediction. Import the first batch of monitoring data into the constraint model, and perform the prediction of remaining oil for the second year. Compare the prediction result with the second batch of monitoring data. If the difference is <10%, it is considered that the number of wells in the second batch of monitoring schemes is the optimal number of wells, and there is no need to increase the monitoring wells and monitoring frequency.

[0063] Embodiment 3

[0064] In a specific Embodiment 3 of applying the present invention, as Figure 2 shown, the guidance on the monitoring frequency of dynamic monitoring wells by the reservoir remaining oil saturation inversion method based on dynamic monitoring data of the present invention specifically includes:

[0065] Step 1: Perform the prediction for the second year based on the corrected model, and compare the prediction result with the actual result of the second year, so as to guide the monitoring frequency of dynamic monitoring wells.

[0066] Predict the model and compare with the actual data after prediction. Import the first batch of monitoring data into the constraint model, and perform the prediction of remaining oil for the second year. Compare the prediction result with the second batch of monitoring data. If the difference is >10%, then encrypt the monitoring wells and increase the monitoring frequency. At the same time, predict the remaining oil distribution for the third year and compare with the third batch of monitoring data. If the difference is not significant, then it is considered that the number of wells in the third batch of monitoring schemes is the optimal number of wells.

[0067] Based on fine history matching, the present invention analyzes the remaining oil and gas saturation field and the remaining oil and gas abundance data field, classifies the types of remaining potential, clarifies the main controlling factors of various types of remaining potential, and predicts the favorable areas of oil and gas distribution. Through numerical simulation history matching work, combined with dynamic monitoring data, the production dynamic characteristics and production dynamic indicators are fitted to obtain a three-dimensional numerical simulation model that can characterize the current oil, gas and water distribution, and further guide the monitoring frequency of dynamic monitoring wells and carry out the evaluation of remaining oil and gas distribution and remaining potential.

[0068] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0069] Except for the technical features described in the specification, the rest are well-known technologies to those skilled in the art.

Claims

1. A method for inverting the remaining oil saturation of a reservoir based on dynamic monitoring data, characterized in that: The reservoir remaining oil saturation inversion method based on dynamic monitoring data includes: Step 1, collect geological data; Step 2, establishing a three-dimensional fine geological model; Step 3, correcting the three-dimensional fine geological model; Step 4: Delineate the fluid potential field based on the oil and gas migration channel and migration law to obtain the distribution characteristics of the remaining oil; Step 5: predict and compare the actual data to obtain the monitoring frequency of the dynamic monitoring well.

2. The method for inversion of remaining oil saturation in a reservoir based on dynamic monitoring data according to claim 1, characterized in that: In step 1, existing structural, stratigraphic, sedimentary and physical property data are collected to determine characteristic parameters required to characterize the distribution of remaining oil, and corresponding constraint conditions are determined within the characteristic parameters according to the product phase.

3. The method for determining the characteristic parameters required for characterizing the residual oil distribution according to claim 2, characterized in that: In step 1, the faults are reinterpreted based on seismic coherence attributes, the faults in the study area are re-identified, and the top surface structural map of the oil group is generated through velocity field time-depth conversion and actual drilling stratification correction. This is used as a constraint to generate the top surface structure of each rhythmic segment within the oil group.

4. The method for inversion of remaining oil saturation in reservoirs based on dynamic monitoring data according to claim 3 is characterized in that: In step 1, a high-resolution sequence stratigraphic method is used, with cycle comparison, hierarchical control, well-seismic combination, and multi-dimensional interaction as the guiding principles for stratification. Based on the regional marker layers, auxiliary marker layers, curve morphological characteristics, and the principle of formation thickness changes, a fine stratigraphic comparison of the oil group is carried out, and an isochronous stratigraphic framework for each sublayer within the oil group in the study area is established to clarify the lithology, thickness, distribution characteristics, and changing laws of the strata and oil layers.

5. The three-dimensional fine geological model according to claim 4, characterized in that: In step 1, based on the isochronous stratigraphic division and comparison, the regional geological background is integrated, the core wells are analyzed in detail, and the sedimentary microfacies types of the sand bodies are determined through vertical sequence analysis, single indicator phase analysis, and sedimentary cycle analysis, and then a typical sedimentary microfacies column chart is established; then, based on the logging phase analysis, the response relationship between the sedimentary microfacies and the logging curve is established, the sedimentary microfacies of the entire area are divided, and the distribution characteristics and combination relationships of the sedimentary microfacies are studied to finally establish the sedimentary model of the area.

6. The three-dimensional fine geological model according to claim 5, characterized in that: In step 1, the reservoir plane, section microscopic characteristics and heterogeneity characteristics are studied through systematic analysis of core observation description, thin section identification, scanning electron microscopy, mercury injection phase permeability curve and well logging data; Study the planar distribution characteristics of diagenetic phases and deepen the understanding of reservoirs.

7. The three-dimensional fine geological model according to claim 6, characterized in that: In step 1, the rock type and interstitial material content are studied to clarify the petrological characteristics of the reservoir and compile a planar distribution map of microscopic mineral components; Conduct reservoir diagenesis research, analyze diagenesis types and their impact on reservoir properties, and compile diagenetic facies plane distribution maps; Conduct research on reservoir pore structure, pore type and connectivity; conduct research on reservoir physical property distribution characteristics and heterogeneity, compile plane distribution maps, and formulate reservoir classification standards and comprehensive evaluations.

8. The three-dimensional fine geological model according to claim 1, characterized in that: In step 2, based on the characteristic parameters and constraints, and taking the logging data as the basis, the attribute parameters of porosity, permeability and saturation of each well point are corrected in combination with the well test data to establish a three-dimensional fine geological model that can fully reflect the structural characteristics, sand body distribution characteristics and physical property distribution characteristics of the well area.

9. The three-dimensional fine geological model according to claim 8, characterized in that: In step 2, the model includes structural and layer models, deterministic sedimentary microfacies models, reservoir lithofacies models under sedimentary microfacies constraints, and porosity, permeability and saturation models controlled by sedimentary microfacies.

10. The method for inverting the remaining oil saturation of a reservoir based on dynamic monitoring data according to claim 1, characterized in that: In step 3, the three-dimensional fine geological model is dynamically modified in combination with the actual dynamic monitoring data, and the three-dimensional fine geological model is sliced ​​and partitioned based on the aforementioned constraints, and oil and gas migration channels are established for individual slice partitions according to the lithofacies characteristics within the individual slice partitions.

11. The method for inversion of remaining oil saturation in a reservoir based on dynamic monitoring data according to claim 1, characterized in that: In step 4, in the dynamically corrected three-dimensional fine geological model, the fluid potential field is delineated in combination with the oil and gas migration channels and migration laws, so as to accurately obtain the distribution characteristics of the remaining oil.

12. The method for inversion of remaining oil saturation in reservoirs based on dynamic monitoring data according to claim 11, characterized in that: In step 4, the reserve calculation is performed based on the established geological model. In the process of reserve calculation, the original geological reserves are calculated in the model using parameters such as porosity, net-to-gross ratio, and oil-gas-water interface, based on the calculation principle of using small layers as units in the vertical direction and sand bodies as units in the horizontal direction.

13. The method for inverting the remaining oil saturation of a reservoir based on dynamic monitoring data according to claim 1, characterized in that: In step 5, a prediction for the second year is performed based on the revised model, and the prediction result is compared with the actual result for the second year to guide the monitoring frequency of the dynamic monitoring wells.

14. The method for inverting the remaining oil saturation of a reservoir based on dynamic monitoring data according to claim 13, characterized in that: In step 5, the monitoring frequency of dynamic monitoring wells is guided: the first batch of monitoring data is imported into the constraint model, and the remaining oil in the second year is predicted. The prediction results are compared with the second batch of monitoring data. If the difference is large, the monitoring intensity is increased, and the remaining oil distribution in the third year is predicted and compared with the second batch of monitoring data. If the difference is not large, then the number of wells in the second batch of monitoring plan is considered to be the critical optimized number of wells.

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