River channel superimposed pattern quantitative evaluation method and storage medium

Abstract

The application discloses a river channel superimposed pattern quantitative evaluation method and a storage medium, and the method comprises the following steps: a modeling step: extracting a typical river channel superimposed pattern and characteristic parameters, and establishing a three-dimensional river channel model; a pattern chart establishing step: performing a shut-in pressure recovery simulation according to the three-dimensional river channel model to obtain a river channel superimposed pattern chart; a parameter chart establishing step: performing a three-dimensional river channel model pressure simulation by changing river channel parameters to obtain different river channel parameter charts; and an evaluation step: performing river channel superimposed pattern quantitative evaluation through the river channel superimposed pattern chart and the different river channel parameter charts. The application improves the accuracy of river channel superimposed pattern evaluation through quantitative evaluation of the river channel superimposed pattern.

Description

Technical Field

[0001] This invention relates to the field of fine reservoir characterization technology, and in particular to a method and storage medium for quantitative evaluation of channel overlay patterns. Background Technology

[0002] Deep continental reservoirs are highly heterogeneous, with frequent shifts during channel deposition, rapid facies changes, and complex internal stacking patterns and structures. This poses significant challenges to the detailed description and evaluation of reservoir configurations, especially for offshore oilfields. Given the high investment and risks in exploration and evaluation, low seismic quality, large well spacing, and limited data, the process of recognizing sand body reserves and conducting rolling evaluations is greatly restricted, affecting the deployment of injection and production well networks and effective development of the reservoir.

[0003] In the early stages of development, the detailed characterization of terrestrial channel sand bodies mainly relied on seismic, well logging, and sedimentary methods to study reservoir architecture. This approach required a high level of data foundation, was relatively macroscopic, and presented some ambiguity in terms of sand body stacking patterns and models. As development progressed, dynamic response provided better validation support for more accurate evaluation of reservoir distribution. Currently, there are two main methods for evaluating sand body distribution using dynamic methods: one is to evaluate sand body connectivity using injection-production dynamic response, which mainly judges sand body stacking relationships from a qualitative perspective; the other is to conduct analytical or numerical well tests using pressure recovery test data. Analytical well tests are more focused on evaluating composite physical property boundaries and cannot accurately assess sand body stacking patterns, while numerical well tests are more based on two-dimensional numerical models, which are difficult to construct intricate and complex three-dimensional geological bodies. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address at least one deficiency of the related technologies mentioned in the background: the inability to accurately evaluate the three-dimensional channel overlay pattern, and to provide a quantitative evaluation method and storage medium for channel overlay patterns.

[0005] The technical solution adopted by this invention to solve its technical problem is: to construct a quantitative evaluation method for river channel superposition patterns, which includes the following steps:

[0006] In some embodiments, the modeling steps are: extracting typical river channel overlay patterns and feature parameters, and establishing a three-dimensional river channel model;

[0007] Steps for creating the style template: Perform a shutdown pressure recovery simulation based on the 3D river channel model to obtain the river channel overlay style template;

[0008] Steps to create parameter charts: By changing the river parameters, perform pressure simulation of the three-dimensional river model to obtain charts with different river parameters;

[0009] Evaluation steps: Quantitative evaluation of river channel overlay patterns is conducted using river channel overlay pattern maps and maps with different river channel parameters.

[0010] In some embodiments, the step of creating a style template includes:

[0011] The pressure recovery simulation of the shutdown was carried out based on the three-dimensional river channel model, and the pressure recovery derivative curve was obtained. The river channel overlay pattern was determined based on the pressure recovery derivative curve.

[0012] In some embodiments, the river channel stacking style includes: isolated river channel, stacked river channel, and side-stacked river channel.

[0013] In some embodiments, the step of establishing the parameter map includes:

[0014] By varying the river channel width, a three-dimensional river channel model was used to simulate the pressure recovery during closure, resulting in double logarithmic pressure recovery curves for different river channel widths; or...

[0015] By changing the river channel width, a three-dimensional river channel model was used to simulate the pressure reduction, resulting in double logarithmic curves of pressure reduction for different river channel widths.

[0016] In some embodiments, the evaluation step may be preceded by:

[0017] Obtain the time of occurrence of the boundary point of the pressure recovery derivative curve in the pressure recovery double logarithmic curve chart for different river widths;

[0018] Establish the relationship between the time of occurrence of the boundary point of the pressure recovery derivative curve and the channel width.

[0019] In some embodiments, the evaluation step may be preceded by:

[0020] Obtain the time when the boundary point of the derivative curve of pressure reduction appears in the double logarithmic curve plot of pressure reduction for different river widths;

[0021] Establish the relationship between the time of occurrence of the boundary point of the pressure reduction derivative curve and the river width.

[0022] In some embodiments, the boundary point of the pressure recovery derivative curve is the lowest point of the concave part of the pressure recovery derivative curve;

[0023] The boundary point of the pressure reduction derivative curve is the point where the slope of the pressure reduction derivative curve is 1.

[0024] In some embodiments, the evaluation step includes:

[0025] Obtain the pressure recovery derivative curve under the pressure recovery of the river channel closure, and determine the river channel overlay pattern by comparing the feature of the pressure recovery derivative curve with the pressure recovery derivative curve of the river channel overlay pattern map.

[0026] The occurrence time of the boundary point of the pressure recovery derivative curve of the river channel is obtained. The river channel width is determined by the relationship between the occurrence time of the boundary point of the pressure recovery derivative curve and the river channel width, thus completing the quantitative evaluation of the river channel overlay pattern.

[0027] In some embodiments, the evaluation step includes:

[0028] Obtain the pressure recovery derivative curve under the pressure recovery of the river channel closure, and determine the river channel overlay pattern by comparing the feature of the pressure recovery derivative curve with the pressure recovery derivative curve of the river channel overlay pattern map.

[0029] The occurrence time of the boundary point of the pressure reduction derivative curve of the river channel is obtained. The river channel width is determined by the relationship between the occurrence time of the boundary point of the pressure reduction derivative curve and the river channel width, thus completing the quantitative evaluation of the river channel overlay pattern.

[0030] The present invention also constructs a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described method for quantitative evaluation of river channel overlay patterns.

[0031] By implementing this invention, the following beneficial effects are achieved:

[0032] This invention employs the following steps: modeling: extracting typical river channel overlay patterns and characteristic parameters to establish a three-dimensional river channel model; pattern template creation: performing shutdown pressure recovery simulation based on the three-dimensional river channel model to obtain river channel overlay pattern templates; parameter template creation: performing pressure simulation of the three-dimensional river channel model by changing river channel parameters to obtain templates with different river channel parameters; and evaluation: quantitatively evaluating river channel overlay patterns using the river channel overlay pattern templates and templates with different river channel parameters, thereby improving the accuracy of river channel overlay pattern evaluation. Attached Figure Description

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0034] Figure 1 A flowchart of an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention is shown;

[0035] Figure 2-a This invention illustrates a three-dimensional perspective view of a river channel geological body, representing an embodiment of the quantitative evaluation method for river channel overlay patterns according to the present invention. Figure 2-b This invention illustrates a three-dimensional profile of the physical properties of a river channel geological body, representing an embodiment of the quantitative evaluation method for river channel overlay patterns according to the present invention.

[0036] Figure 3-a An isolated river pattern is shown as an embodiment of the quantitative evaluation method for river overlay patterns of the present invention; Figure 3-bThis invention illustrates an embodiment of the quantitative evaluation method for river channel overlay patterns, showing an isolated river channel pressure recovery double logarithmic curve.

[0037] Figure 4-a This invention illustrates a stacked river pattern according to an embodiment of the quantitative evaluation method for river stacking patterns of the present invention; Figure 4-b This invention illustrates a double logarithmic curve of pressure recovery in a stacked river channel according to an embodiment of the quantitative evaluation method for river channel stacking patterns of the present invention.

[0038] Figure 5-a This invention illustrates a side-stacked river pattern as an embodiment of the quantitative evaluation method for river channel stacking patterns of the present invention; Figure 5-b This invention illustrates a double logarithmic curve of pressure recovery in a side-stacked river channel according to an embodiment of the quantitative evaluation method for river channel stacking patterns of the present invention.

[0039] Figure 6-a This invention illustrates double logarithmic curves of pressure recovery under different channel widths in an embodiment of the quantitative evaluation method for channel overlay patterns of the present invention. Figure 6-b This invention illustrates double logarithmic curves of pressure reduction under different channel widths in an embodiment of the quantitative evaluation method for channel overlay patterns of the present invention.

[0040] Figure 7-a This invention illustrates double logarithmic curves of pressure recovery for a side-stacked river channel with different stacking thicknesses, according to an embodiment of the quantitative evaluation method for river channel stacking patterns of the present invention. Figure 7-b This invention illustrates double logarithmic curves of pressure recovery under different stacked physical properties in a side-stacked river channel according to an embodiment of the quantitative evaluation method for river channel stacking patterns of the present invention.

[0041] Figure 8 This paper illustrates the relationship between different channel widths and the occurrence time of boundary points of the pressure reduction derivative curve or the pressure recovery derivative curve in an embodiment of the quantitative evaluation method for channel overlay patterns of the present invention.

[0042] Figure 9-a This invention illustrates a double logarithmic curve of pressure recovery at layer 2900 during the trial production stage of well 10a in the X oilfield, according to an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention. Figure 9-b This invention illustrates a double logarithmic curve of pressure recovery at layer 2890 during the trial production stage of well 10a in the X oilfield, according to an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention. Figure 9-c This invention illustrates a double logarithmic curve of pressure recovery at layer 2880 during the trial production stage of well 10a in the X oilfield, according to an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention. Figure 9-d This invention illustrates a double logarithmic curve of pressure recovery at layer 2850 during the trial production stage of well 10a in the X oilfield, according to an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention.

[0043] Figure 10This invention illustrates a double logarithmic curve of actual production pressure reduction in well 4H3 of oilfield X, according to an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention.

[0044] Figure 11-a This invention illustrates a post-drilling oil-bearing area map of well 4H3 in the X oilfield, based on an embodiment of the quantitative evaluation method for river channel overlay patterns. Figure 11-b The diagram shows the oil-bearing area of ​​the X oilfield after the addition of the 17S1 directional well in an embodiment of the quantitative evaluation method for river channel overlay patterns of the present invention. Detailed Implementation

[0045] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0046] It should be noted that the flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0047] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0048] like Figure 1 As shown, some embodiments of the present invention disclose a method for quantitative evaluation of river channel overlay patterns, the method comprising the following steps:

[0049] Modeling steps: Extract typical river channel overlay patterns and feature parameters, and establish a three-dimensional river channel model;

[0050] Steps for creating the style template: Perform a shutdown pressure recovery simulation based on the 3D river channel model to obtain the river channel overlay style template;

[0051] Steps to create parameter charts: By changing the river parameters, perform pressure simulation of the three-dimensional river model to obtain charts with different river parameters;

[0052] Evaluation steps: Quantitative evaluation of river channel overlay patterns is conducted using river channel overlay pattern maps and maps with different river channel parameters.

[0053] As shown in Figure 2, based on the geological knowledge base of the target area and the basic understanding of reservoir configuration research, typical channel superposition patterns and characteristic parameters, such as channel width, thickness, physical property levels, and channel lateral permeability, are extracted to establish corresponding three-dimensional channel geological body mechanism models and reservoir models. Among these, Figure 2-a A three-dimensional geological model of the river channel. Figure 2-b This is a three-dimensional profile of the physical properties of river channel geological bodies.

[0054] In some embodiments, the step of establishing a style pattern includes: performing a shutdown pressure recovery simulation based on a three-dimensional river channel model to obtain a pressure recovery derivative curve, and determining a river channel overlay style pattern based on the pressure recovery derivative curve.

[0055] In some embodiments, the river channel stacking styles include: isolated river channels, stacked river channels, and side-stacked river channels.

[0056] As shown in Figure 3, the isolated river channel pattern is as follows: Figure 3-a As shown, the double logarithmic curve of pressure recovery in isolated river channels is as follows: Figure 3-b As shown, the upper line is the pressure change curve of pressure recovery, and the lower line is the pressure recovery derivative curve. It shows that after radial flow begins, when it encounters the channel, the supply of superimposed sand bodies is weak, and the pressure recovery derivative curve rises sharply.

[0057] As shown in Figure 4, the stacked river channel pattern is as follows: Figure 4-a As shown, the double logarithmic curves of pressure recovery in stacked river channels are as follows: Figure 4-b As shown, the upper line is the pressure change curve of pressure recovery, and the lower line is the pressure recovery derivative curve. It shows that after radial flow, the pressure recovery derivative curve rises slightly due to the influence of the small superimposed side edge. As the outer superimposed channel supplies water rapidly, the pressure recovery derivative curve drops.

[0058] As shown in Figure 5, the side-overlapping river channel pattern is as follows: Figure 5-a As shown, the double logarithmic curve of pressure recovery in side-stacking channels is as follows: Figure 5-b As shown, the upper line is the pressure change curve of pressure recovery, and the lower line is the pressure recovery derivative curve, which presents five stages. Compared with the composite model in traditional analytical well testing, two more stages are added: Stage 3 provides a more detailed three-dimensional channel model of the changes in supply from the channel flanks, and the pressure recovery derivative curve shows a certain "concave" phenomenon; Stage 5 shows that the pressure recovery derivative curve decreases as the pressure is transmitted to the outer channel.

[0059] In some embodiments, the step of creating a parameter chart includes:

[0060] By varying the river channel width, a three-dimensional river channel model was used to simulate the pressure recovery during closure, resulting in double logarithmic pressure recovery curves for different river channel widths; or...

[0061] By changing the river channel width, a three-dimensional river channel model was used to simulate the pressure reduction, resulting in double logarithmic curves of pressure reduction for different river channel widths.

[0062] For the time step setting of the simulation of production pressure reduction and shutdown pressure recovery of production wells, hourly step size is used during the well opening production stage, second-level step size is used from one day to two days before shutdown, and minute or hourly step size can be used after three days of shutdown, so as to meet the accuracy requirements of the double logarithmic curve chart of pressure reduction and the double logarithmic curve chart of pressure recovery for data points.

[0063] The evaluation step is preceded by: obtaining the occurrence time of the boundary point of the pressure recovery derivative curve in the pressure recovery double logarithmic curve chart for different channel widths; and establishing the relationship between the occurrence time of the boundary point of the pressure recovery derivative curve and the channel width. Alternatively,

[0064] The evaluation step is preceded by: obtaining the occurrence time of the boundary point of the derivative curve of pressure reduction in a double logarithmic curve chart for different river widths; and establishing the relationship between the occurrence time of the boundary point of the derivative curve of pressure reduction and the river width.

[0065] Simulations of pressure reduction during production and pressure recovery during shutdown of production wells are conducted, and pressure change curves are output, including pressure change curves for pressure reduction and pressure change curves for pressure recovery. The derivative curve for pressure reduction is obtained by differentiating the pressure change curve for pressure reduction, and the derivative curve for pressure recovery is obtained by differentiating the pressure change curve for pressure recovery.

[0066] In some embodiments, the boundary point of the pressure recovery derivative curve is the lowest point of the depression in the pressure recovery derivative curve; the boundary point of the pressure reduction derivative curve is the point where the slope of the pressure reduction derivative curve is 1.

[0067] The time when the slope of the pressure reduction derivative curve is 1 indicates the time when the pressure is transmitted to the riverbank; the time when the lowest point of the depression in the pressure recovery derivative curve (the "concave" curve curves upwards) indicates the time when the pressure is transmitted to the riverbank.

[0068] Figure 9 shows a double logarithmic curve of pressure recovery for different channel widths under conditions of pressure recovery during shutdown and pressure reduction during production, achieved by varying the width of the main channel. Figure 6-a (as shown) and double logarithmic curves of pressure reduction at different channel widths (as shown) Figure 6-bAs shown in the comparison, for the case of pressure recovery after shutdown, the wider the river channel and the more abundant the supply on the side of the river channel, the deeper the "concave" of the pressure recovery derivative curve, and the later the pressure is transmitted to the side of the river channel, the later the boundary point of the pressure recovery derivative curve appears; for the case of reduced production pressure, the wider the river channel and the later the pressure is transmitted to the boundary of the river channel and the quasi-stable stage appears, the later the boundary point of the pressure reduction derivative curve appears.

[0069] like Figure 7-a As shown, in some embodiments, the step of establishing the parameter chart further includes: by changing the channel overlay thickness, performing a three-dimensional channel model shutdown pressure recovery simulation to obtain a double logarithmic curve chart of pressure recovery for different channel overlay thicknesses;

[0070] The evaluation steps also include: quantitatively evaluating the channel overlay pattern using channel overlay pattern charts and double logarithmic curve charts of pressure recovery for different channel overlay thicknesses.

[0071] like Figure 7-b As shown, in some embodiments, the step of establishing the parameter chart further includes: by changing the superimposed properties of the river channel, performing a three-dimensional river channel model shutdown pressure recovery simulation, and obtaining a double logarithmic curve chart of pressure recovery for different superimposed properties of the river channel.

[0072] The evaluation steps also include: quantitatively evaluating the channel overlay patterns using channel overlay pattern diagrams and logarithmic curve diagrams of pressure recovery for different channel overlay properties.

[0073] By changing the channel stacking parameters, a comparative analysis of the double logarithmic curves of pressure recovery under the pressure recovery conditions after shutdown was conducted. Taking a side-stacked channel as an example, by changing the distribution thickness and physical properties of the sand bodies on the channel flanks, it can be seen that the degree of stacking has a significant impact on the pressure recovery derivative curve. As the thickness of the channel flanks decreases or the physical properties of the channel stacking area become worse, the pressure recovery derivative curve shows a greater upward tilt after radial flow under the pressure recovery conditions after shutdown, indicating a weaker sand body connectivity.

[0074] In some embodiments, the evaluation step includes:

[0075] Obtain the pressure recovery derivative curve under the pressure recovery of the river channel closure, and determine the river channel overlay pattern by comparing the feature of the pressure recovery derivative curve with the pressure recovery derivative curve of the river channel overlay pattern map.

[0076] The occurrence time of the boundary point of the pressure recovery derivative curve of the river channel is obtained. The river channel width is determined by the relationship between the occurrence time of the boundary point of the pressure recovery derivative curve and the river channel width, thus completing the quantitative evaluation of the river channel overlay pattern.

[0077] In some embodiments, the evaluation step includes:

[0078] Obtain the pressure recovery derivative curve under the pressure recovery of the river channel closure, and determine the river channel overlay pattern by comparing the feature of the pressure recovery derivative curve with the pressure recovery derivative curve of the river channel overlay pattern map.

[0079] The occurrence time of the boundary point of the pressure reduction derivative curve of the river channel is obtained. The river channel width is determined by the relationship between the occurrence time of the boundary point of the pressure reduction derivative curve and the river channel width, thus completing the quantitative evaluation of the river channel overlay pattern.

[0080] like Figure 8 As shown, after establishing the relationship between the river width and the occurrence time of the boundary points of the pressure reduction derivative curve or the pressure recovery derivative curve, the river width can be quickly estimated by obtaining the occurrence time of the boundary points of the pressure reduction derivative curve or the pressure recovery derivative curve.

[0081] For example, this embodiment provides a method for quantitative evaluation of river channel overlay patterns. This method is merely an example and is not intended to limit the scope of this application. Other methods may also be used, as detailed below:

[0082] I. Evaluation of Channel Overlay Patterns. Taking the distribution of Paleogene continental reservoir sand bodies and the assessment of reserves in the X oilfield as an example, the deep Paleogene of the X oilfield is a braided river delta sedimentary system. The thickness of sand bodies in this sedimentary environment changes rapidly and the overlay relationships are complex. As the number of actual drilling wells gradually increases, the contradictions in sand body overlay become more prominent, the oil-water relationship is complex, and the oil-bearing range is scattered.

[0083] During the 10-year trial production phase of the development and evaluation well in this block, layered shut-in pressure recovery tests were conducted from deep to shallow, as shown in Figure 11. Double logarithmic pressure recovery curves were obtained for different layers. These curves were compared with the pressure recovery derivative curves for different channel superposition types in the above embodiments. Figure 9-a As shown, the pressure recovery derivative curve of layer 2900 drops in the latter part, exhibiting a stacked pattern; as Figure 9-b As shown, the pressure recovery derivative curve of layer 2890 is flat in the latter part, exhibiting a side-stacking pattern; as Figure 9-c and Figure 9-d As shown, the pressure recovery derivative curves of layers 2880 and 2850 show an upward curve in the latter part, indicating an isolated type. Further analysis guides the understanding that the braided river delta sedimentary system in this block can be divided into three stages: ① thick-layered braided river channel zone (layer 2900 and below); ② gradually thinning underwater distributary channels dominated by lateral or shear stacking (layers 2900–2880); ③ thin-layered isolated underwater distributary channels-sheet sand bodies (layers 2880–2850).

[0084] II. Quantitative Analysis of Channel Overlap Patterns. Based on the previous sand body model, the 2875 reservoir in this block is considered to be mainly composed of thin, isolated underwater distributary channels and sheet-like sand bodies. The reservoir thickness after drilling the early 4H3 well was 6.5 meters. The oil-bearing area was delineated according to the principle of half the well spacing (120-250m), indicating a small scale. After the well was put into production, the production capacity was high and the effect was good, suggesting that the reserve base is underestimated.

[0085] A three-dimensional geological model was established, and simulations of pressure reduction were conducted by varying the river channel width. Double logarithmic curves of pressure reduction under different channel widths were obtained. Boundary points of the pressure reduction derivative curves were selected, and the time points where the slope of the curve reached 1 were identified as the pseudo-steady-state time points at the sand body boundary. The relationship between the river channel width and the boundary points was then established. Figure 8 As shown.

[0086] like Figure 10 As shown, the actual production process pressure data of well 4H3, which requires quantitative analysis, was converted into a double logarithmic curve of pressure reduction. The boundary point of the pressure reduction derivative curve, i.e., the point with a slope of 1, was read at 300 hours. Analysis of Figure 11 indicates that well 4H3 meets the criteria of a river channel width exceeding 500 meters, while the original well control delineation range of 120 to 250 meters is as follows... Figure 11-a As shown, the channel width determined by quantitative analysis exceeds the originally well-controlled delineation range; therefore, as Figure 11-b As shown, a directional well 17S1 was drilled within 400 meters of well 4H3. The actual drilling of the target reservoir revealed an oil column of 5.7 meters, confirming the expansion of the sand body area and providing a quantitative analysis of the channel superposition pattern.

[0087] This invention provides a research method for characterizing pressure recovery or production pressure drop in arbitrary three-dimensional geological bodies through precise numerical simulation at the millisecond level. It generates double logarithmic curves for pressure recovery or pressure reduction under different three-dimensional channel model overlay patterns, enabling the characterization of characteristic quantities under variations in sand body distribution and internal overlay parameters. This expands upon traditional well testing methods, overcoming the bottleneck of traditional numerical well testing being limited by existing software modules and hindering convenient numerical well testing of complex three-dimensional geological bodies. Furthermore, compared to traditional double logarithmic curves, it enriches the characteristic charts of pressure derivative changes and quantitative parameter characterization methods for three-dimensional channel geological bodies.

[0088] Some embodiments of the present invention disclose a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it implements the quantitative evaluation method for river channel overlay patterns as described in any of the above embodiments, which will not be elaborated further here.

[0089] It is understood that the above embodiments only illustrate some implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can freely combine the above embodiments or technical features without departing from the concept of the present invention, and can also make several modifications and improvements, all of which fall within the protection scope of the present invention. That is, the embodiments described "in some embodiments" can be freely combined with any of the preceding and following embodiments. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.

Claims

1. A method for quantitative evaluation of river channel overlay patterns, characterized in that, The method includes the following steps: Modeling steps: Extract typical river channel overlay patterns and feature parameters, and establish a three-dimensional river channel model; The steps for creating the style template are as follows: Based on the 3D river channel model, a shutdown pressure recovery simulation is performed to obtain the river channel overlay style template, which includes: based on the 3D river channel model, a shutdown pressure recovery simulation is performed to obtain the pressure recovery derivative curve, and the river channel overlay style template is determined based on the pressure recovery derivative curve. Steps to create parameter charts: By changing the river parameters, perform pressure simulation of the three-dimensional river model to obtain charts with different river parameters; Evaluation steps: Quantitative evaluation of channel overlay patterns is conducted using channel overlay pattern maps and maps with different channel parameters; The evaluation steps include: obtaining the pressure recovery derivative curve under the pressure recovery after river closure; comparing its features with the pressure recovery derivative curve of the river overlay pattern map to determine the river overlay pattern; obtaining the occurrence time of the boundary points of the pressure recovery derivative curve of the river; determining the river width by the relationship between the occurrence time of the boundary points of the pressure recovery derivative curve and the river width; and completing the quantitative evaluation of the river overlay pattern. Alternatively... Obtain the pressure recovery derivative curve under the pressure recovery of the river channel closure. By comparing the feature of the pressure recovery derivative curve with the pressure recovery derivative curve of the river channel overlay pattern, the river channel overlay pattern is determined. Obtain the occurrence time of the boundary point of the pressure reduction derivative curve of the river channel. By the relationship between the occurrence time of the boundary point of the pressure reduction derivative curve and the river channel width, the river channel width is determined, and the quantitative evaluation of the river channel overlay pattern is completed. Wherein, the boundary point of the pressure recovery derivative curve is the lowest point of the concave part of the pressure recovery derivative curve; the boundary point of the pressure reduction derivative curve is the point where the slope of the pressure reduction derivative curve is 1.

2. The method for quantitative evaluation of river channel overlay patterns according to claim 1, characterized in that, The river channel stacking styles include: isolated river channels, stacked river channels, and side-stacked river channels.

3. The quantitative evaluation method for river channel overlay patterns according to claim 1, characterized in that, The steps for creating the parameter chart include: By varying the river channel width, a three-dimensional river channel model was used to simulate the pressure recovery during closure, resulting in double logarithmic pressure recovery curves for different river channel widths; or... By changing the river channel width, a three-dimensional river channel model was used to simulate the pressure reduction, resulting in double logarithmic curves of pressure reduction for different river channel widths.

4. The quantitative evaluation method for river channel overlay patterns according to claim 3, characterized in that, The evaluation step is preceded by: Obtain the time of occurrence of the boundary point of the pressure recovery derivative curve in the pressure recovery double logarithmic curve chart for different river widths; Establish the relationship between the time of occurrence of the boundary point of the pressure recovery derivative curve and the channel width.

5. The quantitative evaluation method for river channel overlay patterns according to claim 3, characterized in that, The evaluation step is preceded by: Obtain the time when the boundary point of the derivative curve of pressure reduction appears in the double logarithmic curve plot of pressure reduction for different river widths; Establish the relationship between the time of occurrence of the boundary point of the pressure reduction derivative curve and the river width.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the quantitative evaluation method for river channel overlay patterns as described in any one of claims 1-5.

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