A method and device for simulating a crevasse splay based on river channel connection relationships

Abstract

The present invention relates to a method and device for simulating a crevasse splay based on river channel connection relationships. The method includes: establishing a river channel vector line composed of a set of control nodes, calculating the curvature of each control node, and constructing a three-dimensional river channel model based on the river channel vector line; judging whether a target crevasse splay to be simulated is generated according to the curvature of each control node and a preset crevasse splay generation threshold; judging the connection relationship between the target crevasse splay and the river channel according to prior geological data and determining the type of the target crevasse splay; and simulating the target crevasse splay based on the type of the target crevasse splay and the three-dimensional river channel model. The present invention depicts the crevasse splay based on the characteristics of different types of crevasse splays and the three-dimensional river channel model, simulates various types of crevasse splays in complex fluvial facies, realizes the quantitative characteristic modeling of the connection mode and connection degree of the crevasse splay in the fluvial facies sedimentary sand body, and can provide theoretical guidance for the oilfield well pattern design and the efficient development of remaining oil and gas.

Description

Technical Field

[0001] The present invention relates to the technical field of geological modeling, and particularly to a method and device for simulating crevasse fans based on river channel connection relationships. Background Art

[0002] Crevasse fan deposition is an important part of the river sedimentation system. As a typical sedimentary microfacies in the river sedimentation system, crevasse fans usually form relatively porous and permeable sand bodies, which can be used as production units for oil and gas reservoirs. Practices in the later stages of development of many oil and gas fields have shown that crevasse fan sand bodies are often favorable reservoir spaces for the distribution of remaining oil and gas. In-depth research on crevasse fan deposition is beneficial for tapping potential and increasing reserves in old oil fields and extending the production life of depleted old oil wells.

[0003] The importance of crevasse fan sediments in controlling the connectivity of sand bodies in the river sedimentation system has become one of the main problems in the later-stage research of oil and gas field development. Sand body connectivity, also known as geometric connectivity, refers to the degree of geometric contact between different sand bodies, generally without considering their fluid connectivity. Scholars generally believe that crevasse fan sediments will increase the lateral connectivity of sand bodies and can act as a "bridge" to connect different distributary channel sand bodies within the same water system branch, which can improve the performance of oil reservoirs to a certain extent. However, in special cases, isolated crevasse fan sand bodies may also be formed (such as when the river channel is abandoned after a flood and filled with subsequent muddy sediments), and horizontal wells need to be designed to penetrate these areas to produce oil and gas. Although many studies on crevasse fan deposition have been carried out by domestic and foreign scholars, there is still a lack of a quantitative characterization method for the connectivity mode and connectivity degree of crevasse fan deposition in fluvial facies sedimentary sand bodies.

[0004] Therefore, it is necessary to propose a crevasse fan modeling method and device based on river channel connectivity relationships, which can determine the type of crevasse fan according to the river channel connectivity relationship and quantitatively express the connectivity mode and connectivity degree of the crevasse fan, providing theoretical guidance for oilfield well pattern design and efficient development of remaining oil and gas. Summary of the Invention

[0005] In view of this, the present invention provides a method and device for simulating crevasse fans based on river channel connection relationships to solve the technical problems that the existing technology lacks a quantitative characterization method for the connectivity mode and connectivity degree of crevasse fan deposition in fluvial facies sedimentary sand bodies, resulting in the inability to accurately and objectively simulate crevasse fans and the inability to provide theoretical guidance for oilfield well pattern design and the development of remaining oil and gas.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for simulating crevasse fans based on river channel connection relationships, including:

[0008] Establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line;

[0009] Judge whether a target crevasse fan to be simulated is generated according to the curvature of each control node and a preset crevasse fan generation threshold;

[0010] Determine the connection relationship between the target crevasse fan and the river channel according to prior geological data, and determine the type of the target crevasse fan according to the connection relationship;

[0011] Simulate the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model.

[0012] Further, determining the type of the target crevasse fan according to the connection relationship includes:

[0013] If the target crevasse fan is connected to a single river channel, determine that the crevasse fan is a single-river-channel-connected type crevasse fan;

[0014] If the target crevasse fan is not connected to the river channel, determine that the crevasse fan is an isolated type crevasse fan;

[0015] If the target crevasse fan is connected to multi-period river channels, determine that the crevasse fan is a multi-river-channel-connected type crevasse fan.

[0016] Further, the method for simulating a single-river-channel-connected type target crevasse fan includes:

[0017] Take the control node at the preset crevasse position as the coordinate origin and establish a local plane coordinate system;

[0018] In the local plane coordinate system, depict the target crevasse fan by using a sector. Take the control node as the center of the sector, and determine the range and extension radius of the sector in the horizontal direction, and the thickness change amplitude in the vertical direction according to the preset quantization control parameters;

[0019] Based on the range, extension radius and thickness change amplitude of the sector, add the morphological simulation of the target crevasse fan in the three-dimensional river channel model.

[0020] Further, the method for simulating an isolated type crevasse fan includes:

[0021] Take the control node at the preset crevasse position as the coordinate origin and establish a local plane coordinate system;

[0022] Determine the center moving distance according to prior geological data, and translate the position of the control node according to the center moving distance;

[0023] Using the control node after position translation as the center of the fan, depict the target breach fan with a fan shape, and determine the horizontal range and extension radius of the fan, as well as the thickness change amplitude in the vertical direction, according to the preset quantization control parameters;

[0024] Based on the range, extension radius and thickness change amplitude of the fan, add the morphological simulation of the target breach fan to the three-dimensional river channel model.

[0025] Furthermore, the method for simulating a multi-channel connected breach fan includes:

[0026] Using the control node at the preset breach position as the coordinate origin, simulate the single-channel connected breach fan according to the preset quantization control parameters;

[0027] Judge whether there are control nodes of adjacent channels within the range and extension radius of the single-channel connected breach fan;

[0028] When there are control nodes of adjacent channels within the range and extension radius of the single-channel connected breach fan, assign the single-channel connected breach fan as a multi-channel connected breach fan;

[0029] When there are no control nodes of adjacent channels within the range and extension radius of the single-channel connected breach fan, establish a new adjacent channel within the single-channel connected breach fan according to the preset river channel generation method, and assign the single-channel connected breach fan as a multi-channel connected breach fan.

[0030] Furthermore, establishing a new adjacent channel within the single-channel connected breach fan according to the preset river channel generation method includes:

[0031] Generate random coordinates within the single-channel connected breach fan and a new river channel center line passing through the random coordinates, and establish a new adjacent channel based on the new river channel center line.

[0032] Furthermore, the preset breach fan generation thresholds include a minimum breach curvature threshold and a breach probability threshold;

[0033] Judging whether to generate a target breach fan to be simulated according to the curvature of each control node and the preset breach fan generation thresholds includes:

[0034] When the curvature of the control node is greater than the minimum breach curvature threshold, generate a breach fan probability value, and judge whether the breach fan probability value is greater than the breach probability threshold;

[0035] When the breach fan probability value is greater than the breach probability threshold, simulate the target breach fan.

[0036] Second aspect, the present invention also provides a crevasse fan simulation device based on river channel connection relationship, including:

[0037] An initial model establishment module, configured to establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line;

[0038] A judgment module, configured to judge whether a target crevasse fan to be simulated is generated according to the curvature of each control node and a preset crevasse fan generation threshold;

[0039] A type analysis module, configured to determine the connection relationship between the target crevasse fan and the river channel according to prior geological data, and determine the type of the target crevasse fan according to the connection relationship;

[0040] A simulation module, configured to simulate the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model.

[0041] Third aspect, the present invention also provides an electronic device, including a processor and a memory, where a computer program is stored on the memory, and when the computer program is executed by the processor, the crevasse fan simulation method based on river channel connection relationship according to any one of the above technical solutions is implemented.

[0042] Fourth aspect, the present invention also provides a computer-readable storage medium, used to store computer-readable programs or instructions, and when the programs or instructions are executed by a processor, the steps in the crevasse fan simulation method based on river channel connection relationship in any one of the above implementation manners can be implemented.

[0043] The present invention provides a crevasse fan simulation method and device based on river channel connection relationship. The method first establishes a river channel vector line, calculates the curvature of each control node on the vector line, and constructs a three-dimensional river channel model based on the river channel vector line; secondly, judges whether a target crevasse fan to be simulated is generated according to the curvature of each control node and a preset crevasse fan generation threshold; thirdly, determines the type of the target crevasse fan according to the connection relationship between the target crevasse fan and the river channel; finally, simulates the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model. The present invention judges whether to perform crevasse fan simulation according to the curvature of the control node and the preset crevasse fan generation threshold, simulates the physical process in actual situations where the water flow impact force at the bend of the river channel is strong and easily washes away the river bank to form a breach, thereby forming a crevasse fan; classifies the crevasse fan according to the connection relationship between the crevasse fan and the river channel, depicts the crevasse fan based on the three-dimensional river channel model according to the characteristics of different types of crevasse fans, simulates various types of crevasse fans in complex river facies, realizes the quantitative characteristic modeling of the connection mode and connection degree of crevasse fans in river facies sedimentary sand bodies, and can provide theoretical guidance for oilfield well pattern design and efficient development of remaining oil and gas. Brief Description of the Drawings

[0044] Figure 1 FIG. is a flowchart of a method according to an embodiment of a method for simulating a crevasse fan based on a river channel connection relationship provided by the present invention;

[0045] Figure 2 FIG. is a schematic structural diagram of a river channel vector line according to an embodiment of the present invention;

[0046] Figure 3 FIG. is a schematic diagram of a curvature calculation according to an embodiment of the present invention;

[0047] Figure 4 FIG. is a schematic diagram of assigning unit grids on a cross-section according to an embodiment of the present invention;

[0048] FIG. 5(a) is a schematic diagram of modeling a plane local coordinate system of a single-channel connected crevasse fan provided by the present invention;

[0049] FIG. 5(b) is a schematic diagram of representing each control parameter of a single-channel connected crevasse fan in a plane local coordinate system provided by the present invention;

[0050] FIG. 6(a) is a schematic diagram of modeling a plane local coordinate system of an isolated crevasse fan provided by the present invention;

[0051] FIG. 6(b) is a schematic diagram of representing each control parameter of an isolated crevasse fan in a plane local coordinate system provided by the present invention;

[0052] Figure 7 FIG. is a schematic diagram of modeling a multi-channel connected crevasse fan according to an embodiment of the present invention;

[0053] Figure 8 FIG. is a schematic structural diagram of a crevasse fan simulation device based on a river channel connection relationship according to an embodiment of the present invention;

[0054] Figure 9 FIG. is a schematic structural diagram of an electronic device according to an embodiment of the present invention. Detailed Embodiments

[0055] The following will specifically describe the preferred embodiments of the present invention with reference to the accompanying drawings. The accompanying drawings form a part of this application and are used together with the embodiments of the present invention to explain the principles of the present invention, rather than to limit the scope of the present invention.

[0056] Before introducing the embodiments of the present invention, the inventive concept of this application will be explained first.

[0057] As a typical sedimentary microfacies in the river sedimentary system, crevasse fan deposits usually form sand bodies with relatively high porosity and permeability, which can serve as production units for oil and gas reservoirs. In-depth study of crevasse fan deposits is beneficial for tapping potential and increasing reserves in old oilfields and extending the production life of depleted old oil wells. The formation of crevasse fans usually occurs at the bends of river channels because the water flow impact is strong at bends, easily breaking down the riverbank to form crevasses, and finally forming crevasse fans. Practical geological studies have shown that during the deposition process of meandering rivers, due to the periodic action of floods, it is often easier to generate crevasse fans.

[0058] A meandering river reservoir refers to the underground reservoir formed in the meandering river system, where sediments brought by river movement accumulate and deposit in the riverbed or riverbank area, eventually forming a geological layer with a certain storage capacity. The formation of meandering river reservoirs is closely related to the geomorphic characteristics of meandering rivers. Meandering rivers, also known as snake-like rivers, generally have a single channel, with a sinuosity index > 1.5, relatively stable channels, a low width / depth ratio, generally < 40. Lateral erosion and aggradation cause the riverbed to migrate towards the concave bank, and point bars are formed on the convex bank.

[0059] In many geological studies, it has been found that there are various types of crevasse fan deposits in complex river facies. According to the connectivity pattern, they are divided into the following types: 1. Single-channel connected crevasse fans, that is, there is a connectivity relationship between the crevasse fan and a single channel; 2. Isolated crevasse fans, that is, the crevasse fan is not connected to the channel; 3. Multi-channel connected crevasse fans, that is, there is a connectivity relationship between the crevasse fan and multiple stages of channels. However, the commonly used methods for depicting river facies usually only consider the quantitative relationship between the crevasse fan and the contemporaneous channel when generating crevasse fans, and cannot simulate various types of crevasse fans in complex river facies, and cannot provide theoretical guidance for oilfield well pattern design and efficient development of remaining oil and gas.

[0060] Among them, the commonly used method for depicting river facies includes the Fluvsim method. The ideal river channel pattern depicted by this method, in addition to the background facies, also includes three sedimentary facies types: channel fill, natural levee, and crevasse fan. Its basic idea is: generate several channel centerline nodes according to the main direction of the channel, connect the channel centerline nodes to form the channel centerline, and then establish a channel profile along the channel centerline. The channel profile is horizontally lengthened and stacked in the main direction of the channel to establish a three-dimensional channel model.

[0061] Based on the core idea of Fluvsim modeling, the present invention uses the channel centerline to depict the channel object, determines different types of crevasse fans by quantitatively controlling the positional relationship between the crevasse fan and the channel, and realizes the modeling of crevasse fans according to the characteristics of each type of crevasse fan, making the simulation of crevasse fans more in line with the actual situation and providing theoretical guidance for oilfield well pattern design and efficient development of remaining oil and gas.

[0062] The present invention provides a method, apparatus, electronic device and computer-readable storage device for simulating a crevasse splay based on river channel connection relationships, which will be described separately below.

[0063] Combined with Figure 1 As shown in the figure, a specific embodiment of the present invention discloses a method for simulating a crevasse splay based on river channel connection relationships, including:

[0064] Step S101: Establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line;

[0065] Step S102: Determine whether a target crevasse splay to be simulated is generated according to the curvature of each control node and a preset crevasse splay generation threshold;

[0066] Step S103: Determine the connection relationship between the target crevasse splay and the river channel according to prior geological data, and determine the type of the target crevasse splay according to the connection relationship;

[0067] Step S104: Simulate the target crevasse splay based on the type of the target crevasse splay and the three-dimensional river channel model.

[0068] Compared with the prior art, the method of this embodiment, first, establishes a river channel vector line, calculates the curvature of each control node on the vector line, and constructs a three-dimensional river channel model based on the river channel vector line; second, determines whether a target crevasse splay to be simulated is generated according to the curvature of each control node and a preset crevasse splay generation threshold; third, determines the type of the target crevasse splay according to the connection relationship between the target crevasse splay and the river channel; finally, simulates the target crevasse splay based on the type of the target crevasse splay and the three-dimensional river channel model. The method of the present invention judges whether to perform crevasse splay simulation according to the curvature of the control node and a preset crevasse splay generation threshold, simulates the physical process in which the water flow impact force at the bend of the river channel is strong in actual situations, easily washes away the river channel embankment to form a crevasse, and thus forms a crevasse splay; classifies the crevasse splay according to the connection relationship between the crevasse splay and the river channel, depicts the crevasse splay based on the three-dimensional river channel model according to the characteristics of different types of crevasse splays, simulates various types of crevasse splays in complex fluvial facies, realizes the quantitative characteristic modeling of the connection mode and connection degree of crevasse splays in fluvial facies sedimentary sand bodies, and can provide theoretical guidance for oilfield well pattern design and efficient development of remaining oil and gas.

[0069] As a specific embodiment, in step S101, the river channel vector line is the center line of the river channel, and the control node set is a coordinate set of a series of spatial control nodes. The center line of the river channel is quantitatively represented by the river channel vector line. After the river channel vector line is determined, the spatial position and basic shape of a river channel can be determined. Among them, the generation of the center line of the river channel includes five parameters, namely the starting point, azimuth angle, control node spacing, maximum offset distance, and total length, which are set by the user.

[0070] The following explains each generation parameter:

[0071] The starting point is the first point of the center line of the river channel, that is, the river channel vector line.

[0072] The azimuth angle represents the main direction of the river channel extension. Taking the starting point as the coordinate origin and the due east (E) direction as 0 degrees, the angle corresponding to the rotation counterclockwise to the main direction is the azimuth angle.

[0073] The control node spacing represents the spacing of the river channel control nodes in the main direction. The distance between the scales in the main direction in the river channel vector line diagram is the control node spacing. A control node is generated at a certain interval along the main direction of the river channel.

[0074] The maximum offset distance represents the maximum distance of the control node from the main direction, which is used to limit that the control node must be within a certain range on both sides of the main direction axis. Along the main direction of the river channel, a river channel control node is generated at every control node spacing. The distance of the control node deviating from the main direction is the curvature parameter input by the user. The maximum offset distance also determines the curvature of the river channel. Sampling is performed through a random function between the negative maximum offset distance and the positive maximum offset distance.

[0075] The total length represents the farthest range of the river channel extension. When the distance between the generated river channel control node and the starting point is greater than the total length of the river channel, the generation of the next river channel control node stops.

[0076] So far, the initial control nodes of the center line of the river channel are generated. Based on the initial control nodes of the center line of the river channel by the above method, the vector line is smoothed and encrypted to obtain the center line node set of the river channel, and the node set is the final river channel vector line. As Figure 2 shown, Figure 2 is a schematic diagram of the river channel vector line generated by the above method.

[0077] As a specific embodiment, after the river channel vector line is generated, for each control node on the vector line, the curvature needs to be calculated. The curvature characterizes the bending degree of the river channel and is characterized by two quantitative parameters, namely the curvature direction and the curvature magnitude. As Figure 3As shown in the figure, the curvature of a single control node is calculated as follows: Except for the first and last nodes, each node on the center line has two adjacent nodes. An circumcircle can be obtained from the current node and its two adjacent nodes. The magnitude of the curvature is the reciprocal of the radius of the circumcircle, and the direction of the curvature is from the center of the circle to the current node. The greater the curvature, the more curved the center line of the river channel. If the current node and its two adjacent nodes are collinear and there is no circumcircle, the curvature is 0 and the curvature has no direction.

[0078] During the deposition process of meandering rivers, due to the periodic action of floods, the formation of crevasse fans often occurs at the bends of the river channels because the water flow impact force is strong at the bends, which easily breaks the river bank to form a crevasse and finally forms a crevasse fan.

[0079] To simulate the formation process of crevasse fans, as a preferred embodiment, the preset crevasse fan generation threshold includes a minimum crevasse curvature threshold and a crevasse probability threshold;

[0080] Judging whether to generate a target crevasse fan to be simulated according to the curvature of each said control node and the preset crevasse fan generation threshold includes:

[0081] When the curvature of the control node is greater than the minimum crevasse curvature threshold, a crevasse fan probability value is generated, and it is judged whether the crevasse fan probability value is greater than the crevasse probability threshold;

[0082] When the crevasse fan probability value is greater than the crevasse probability threshold, simulate the target crevasse fan.

[0083] Specifically, whether a crevasse fan is generated has two parameters: the minimum crevasse curvature and the crevasse probability. Only when the curvature is greater than the minimum crevasse curvature can a river channel crevasse occur, thus forming a crevasse fan. Therefore, a minimum curvature threshold is set. If it is greater than the minimum curvature threshold, it means that the river channel is more curved and it is more likely to have a river channel crevasse. Further, when the curvature of the river channel control node is greater than the minimum crevasse curvature, there is a certain probability of generating a crevasse fan. A random number between 0 and 1 is generated through a random function. When the random number is greater than the set crevasse probability, simulate a crevasse fan.

[0084] As a specific embodiment, the method for constructing a three-dimensional river channel model based on the river channel vector line is as follows: Traverse each grid within the river channel range. According to the positional relationship between the grid and the river channel, when the grid is within the river channel, it is assigned a river channel facies. Among them, the specific positional relationship is judged by the distance between a point and a line. The grid can be regarded as a point, and the river channel can be regarded as a line with a certain width. According to the distance formula from a point to a line segment, the distance from the grid to the center line of the river channel can be calculated. If the distance is greater than half of the river channel width, the grid is outside the river channel. If the distance is less than half of the river channel width, further judgment is made on the cross-section.

[0085] Since the model we need to obtain is a three-dimensional grid model, after the unit grid is judged on the plane, it is also necessary to further judge according to the position of the unit grid on the cross-section. As Figure 4 shown, the river channel presents a flat top and convex bottom shape on the cross-section, and the specific shape is determined by the geological parameters of the river channel, including the width and thickness of the river channel, that is: the top width and the maximum thickness of the river channel. For any unit grid, if both the plane and the cross-section are inside the river channel, the unit grid is assigned the river channel facies.

[0086] The specific calculation method on the cross-section is as follows:

[0087]

[0088] where w(y) is the river channel width, c v (y) is the local curvature, is the maximum curvature.

[0089] When a(y) <= 0.5, the depth of the river channel base below the river channel top is calculated as:

[0090]

[0091] where b(y) = -ln(2) / ln(a(y)), w ∈ [0, w(y)]

[0092] When a(y) > 0.5, the depth of the river channel base below the river channel top is calculated as:

[0093]

[0094] where c(y) = -ln(2) / ln(1 - a(y)).

[0095] In order to more accurately simulate various types of crevasse fans existing in complex river facies, first, the connectivity relationship between the target crevasse fan and the river channel is judged through prior geological data, so as to determine the specific type of the crevasse fan to be simulated. As a preferred embodiment, determining the type of the target crevasse fan according to the connectivity relationship includes:

[0096] If the target crevasse fan is connected to a single river channel, determine that the crevasse fan is a single-river-channel-connected crevasse fan;

[0097] If the target crevasse fan is not connected to the river channel, determine that the crevasse fan is an isolated crevasse fan;

[0098] If the target crevasse fan is connected to multi-stage river channels, determine that the crevasse fan is a multi-river-channel-connected crevasse fan.

[0099] As a preferred embodiment, the method for simulating a single-river-channel-connected target crevasse fan includes:

[0100] Taking the control node at the preset breach position as the coordinate origin, a local plane coordinate system is established;

[0101] In the local plane coordinate system, the target breach fan is depicted by a sector. Taking the control node as the center of the sector, the range in the horizontal direction and the extension radius of the sector are determined according to the preset quantization control parameters, as well as the thickness change amplitude in the vertical direction;

[0102] Based on the range, extension radius and thickness change amplitude of the sector, the morphological simulation of the target breach fan is added to the three-dimensional river channel model.

[0103] As a specific embodiment, when it is determined that a single-channel connected breach fan is generated, taking the river channel node at the breach position as the coordinate origin, a local coordinate system is established in the plane. As shown in Fig. 5(a), Fig. 5(a) shows the schematic diagram of the plane local coordinate system modeling of the single-channel connected breach fan. Taking the curvature direction as the x-axis and rotating 90 degrees counterclockwise as the y-axis.

[0104] The breach fan is depicted by a sector. The breach fan has two control parameters in the plane, the sector angle and the sector radius. The angle determines the range of the breach fan, and the radius determines the extension distance of the breach fan. The thickness of the breach fan gradually decreases from the fan root (river channel control node) to the fan edge (sector arc boundary) in the cross-section, and the height of the breach fan gradually decreases outward from the river channel breach (simulating the water flowing to the lower place after the river channel breach). Taking the thickness at the fan root as the control parameter, and the descent amplitude of the breach fan is controlled by the deposition angle parameter θ of the breach fan. As shown in Fig. 5(b), Fig. 5(b) shows the schematic diagram of the representation of each control parameter of the single-channel connected breach fan in the plane local coordinate system.

[0105] Through the above quantitative parameters, for any given grid, it can be judged whether the grid belongs to the breach fan in the plane and cross-section local coordinate systems, and then the corresponding sedimentary facies type is assigned to the grid.

[0106] As a preferred embodiment, the method for simulating an isolated breach fan includes:

[0107] Taking the control node at the preset breach position as the coordinate origin, a local plane coordinate system is established;

[0108] Based on prior geological data, the center movement distance is determined, and the position of the control node is translated according to the center movement distance;

[0109] Taking the control node after position translation as the center of the sector, the target breach fan is depicted by a sector. The range in the horizontal direction and the extension radius of the sector are determined according to the preset quantization control parameters, as well as the thickness change amplitude in the vertical direction;

[0110] Based on the range, extension radius, and thickness variation amplitude of the fan-shaped area, add the morphological simulation of the target crevasse fan to the three-dimensional river channel model.

[0111] As a specific embodiment, the reason for the generation of an isolated crevasse fan is as follows: the slope at the river channel breach is relatively large, and the sediment contained in the river channel is relatively small. After the sediment flushes out of the breach position, it continues to be transported forward until the slope decreases and the sediment accumulates to form an isolated crevasse fan.

[0112] For the quantification of the geometric morphology of the isolated crevasse fan itself, the control parameters of the isolated crevasse fan and the single-channel connected crevasse fan are exactly the same. The difference is that the isolated crevasse fan is not connected to the river channel.

[0113] When simulating the isolated crevasse fan, still take the river channel breach node as the coordinate origin to establish a coordinate system. Only the center of the fan is not located at the coordinate origin, but moves a certain distance along the breach direction, as shown in Figure 6(a). The moving distance includes the horizontal distance and the vertical distance. The specific translation amount is determined by the user according to the geological interpretation data and is input through parameters, as shown in Figure 6(b).

[0114] As a preferred embodiment, the method for simulating a multi-channel connected crevasse fan includes:

[0115] Take the control node at the preset breach position as the coordinate origin, and simulate the single-channel connected crevasse fan according to the preset quantification control parameters;

[0116] Judge whether there are control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan;

[0117] When there are control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan, assign the single-channel connected crevasse fan as a multi-channel connected crevasse fan;

[0118] When there are no control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan, establish a new adjacent river channel within the single-channel connected crevasse fan according to the preset river channel generation method, and assign the single-channel connected crevasse fan as a multi-channel connected crevasse fan.

[0119] As a preferred embodiment, establishing a new adjacent river channel within the single-channel connected crevasse fan according to the preset river channel generation method includes:

[0120] Generate random coordinates within the single-channel connected crevasse fan and a new river channel center line passing through the random coordinates, and establish a new adjacent river channel based on the new river channel center line.

[0121] As a specific embodiment, the multi-channel connected crevasse splay is connected to the contemporaneous distributary channels, and the scale of the crevasse splay is larger than the distance between the two distributary channels, which generally appears near the crevasse reach where the river scale is large and the distance to the adjacent distributary channel is relatively close. To characterize the connection relationship between the multi-channel connected crevasse splay and the channels, it is necessary to judge whether there is another adjacent channel on the basis of the single-channel connected crevasse splay, and the channel node on this adjacent channel is located inside the crevasse splay. Only when there are other channels located inside the crevasse splay that needs to be generated currently, can the multi-channel connected crevasse splay be generated. As Figure 7 shown Figure 7 shows the modeling schematic diagram of the multi-channel connected crevasse splay.

[0122] If the distance between the two channels is too large and no channel node that meets the conditions can be found, first generate a single-channel connected crevasse splay, and then generate a random coordinate inside the crevasse splay, and generate a new channel center line. The new channel center line needs to pass through the random coordinate generated in the crevasse splay. Furthermore, the multi-channel connected crevasse splay can be simulated.

[0123] To better implement the crevasse splay simulation method based on the channel connection relationship in the embodiments of the present invention, on the basis of the crevasse splay simulation method based on the channel connection relationship, correspondingly, please refer to Figure 8 , Figure 8 which is a schematic structural diagram of an embodiment of the crevasse splay simulation device based on the channel connection relationship provided by the present invention. An crevasse splay simulation device 800 based on the channel connection relationship provided by the embodiments of the present invention includes:[[]]

[0124] An initial model establishment module 801, configured to establish a channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional channel model based on the channel vector line;

[0125] A judgment module 802, configured to judge whether to generate a target crevasse splay to be simulated according to the curvature of each control node and a preset crevasse splay generation threshold;

[0126] A type analysis module 803, configured to determine the connection relationship between the target crevasse splay and the channels according to prior geological data, and determine the type of the target crevasse splay according to the connection relationship;

[0127] A simulation module 804, configured to simulate the target crevasse splay based on the type of the target crevasse splay and the three-dimensional channel model.

[0128] It should be noted here that: the corresponding device 800 provided in the above embodiment can implement the technical solutions described in the above method embodiments. The specific implementation principles of the above modules or units can be referred to the corresponding content in the above method embodiments, which will not be elaborated here.

[0129] As shown Figure 9 in the figure above, for the above-mentioned method for simulating a crevasse fan based on river channel connection relationships, the present invention also correspondingly provides an electronic device 900, which may be a computing device such as a mobile terminal, a desktop computer, a notebook, a palm computer, and a server. The electronic device includes a processor 901, a memory 902, and a display 903.

[0130] The memory 902 may be an internal storage unit of the computer device in some embodiments, such as the hard disk or memory of the computer device. The memory 902 may also be an external storage device of the computer device in other embodiments, such as a plug-in hard disk equipped on the computer device, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. Further, the memory 902 may also include both the internal storage unit and the external storage device of the computer device. The memory 902 is used to store application software installed on the computer device and various types of data, such as program codes installed on the computer device. The memory 902 may also be used to temporarily store data that has been output or will be output. In one embodiment, a program 904 for a method for simulating a crevasse fan based on river channel connection relationships is stored on the memory 902, and the program 904 for the method for simulating a crevasse fan based on river channel connection relationships can be executed by the processor 901, thereby implementing the method for simulating a crevasse fan based on river channel connection relationships in various embodiments of the present invention.

[0131] The processor 901 may be a central processing unit (CPU), a microprocessor, or other data processing chips in some embodiments, and is used to run the program codes stored in the memory 902 or process data, such as executing a program for a method for simulating a crevasse fan based on river channel connection relationships.

[0132] The display 903 may be an LED display, a liquid crystal display, a touch liquid crystal display, and an OLED (Organic Light-Emitting Diode) toucher, etc. in some embodiments. The display 903 is used to display information on the computer device and to display a visual user interface. The components 901 - 903 of the computer device communicate with each other through a system bus.

[0133] This embodiment also provides a computer-readable storage medium, on which a program for simulating a crevasse fan based on river channel connection relationships is stored, and when the program for simulating a crevasse fan based on river channel connection relationships is executed by a processor, the steps in the above embodiments can be implemented.

[0134] The present invention provides a method and device for simulating a crevasse fan based on river channel connection relationships. The method first establishes river channel vector lines, calculates the curvature of each control node on the vector lines, and constructs a three-dimensional river channel model based on the river channel vector lines; secondly, determines whether a target crevasse fan to be simulated is generated according to the curvature of each control node and a preset crevasse fan generation threshold; thirdly, determines the type of the target crevasse fan according to the connection relationship between the target crevasse fan and the river channel; and finally, simulates the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model.

[0135] The present invention determines whether to simulate a crevasse fan according to the curvature of the control node and a preset crevasse fan generation threshold, and simulates the physical process in which the water flow impact force at the bend of the river channel is strong in actual situations, easily washes out the river bank to form a breach, and thus forms a crevasse fan; classifies the crevasse fan according to the connection relationship between the crevasse fan and the river channel, depicts the crevasse fan based on the three-dimensional river channel model according to the characteristics of different types of crevasse fans, and simulates various types of crevasse fans in complex fluvial facies, realizing the quantitative characteristic modeling of the connection mode and connection degree of the crevasse fan in the sedimentary sand body of the fluvial facies, and being able to provide theoretical guidance for the design of oilfield well patterns and the efficient development of remaining oil and gas.

[0136] As described above, only the specific preferred embodiments of the present invention are given, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention.

Claims

1. A method for simulating a crevasse splay based on river channel connection relationships, characterized in that, Including: Establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; Judge whether a target breach fan to be simulated is generated according to the curvature of each control node and a preset breach fan generation threshold; Determine the connectivity relationship between the target breach fan and the river channel according to prior geological data, and determine the type of the target breach fan according to the connectivity relationship; If the target breach fan is connected to a single river channel, determine that the breach fan is a single-river-channel-connected type breach fan; Simulate the target breach fan based on the type of the target breach fan and the three-dimensional river channel model; The method for simulating a single-river-channel-connected type target breach fan includes: Taking the control node at the preset breach position as the coordinate origin, establish a local plane coordinate system; Characterize the target breach fan by a sector in the local plane coordinate system, take the control node as the center of the sector, and determine the range and extension radius of the sector in the horizontal direction and the thickness change amplitude in the vertical direction according to preset quantization control parameters; Based on the range, extension radius and thickness change amplitude of the sector, add a morphological simulation of the target breach fan to the three-dimensional river channel model.

2. A method for simulating a crevasse splay based on river channel connection relationships, characterized in that, Including: Establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; Judge whether a target breach fan to be simulated is generated according to the curvature of each control node and a preset breach fan generation threshold; Determine the connectivity relationship between the target breach fan and the river channel according to prior geological data, and determine the type of the target breach fan according to the connectivity relationship; If the target breach fan is not connected to the river channel, determine that the breach fan is an isolated type breach fan; Simulate the target breach fan based on the type of the target breach fan and the three-dimensional river channel model; The method for simulating an isolated type breach fan includes: Taking the control node at the preset breach position as the coordinate origin, establish a local plane coordinate system; Determine the center movement distance based on prior geological data, and translate the position of the control node according to the center movement distance; Taking the control node after position translation as the center of the sector, characterize the target breach fan by a sector, and determine the range and extension radius of the sector in the horizontal direction and the thickness change amplitude in the vertical direction according to preset quantization control parameters; Based on the range, extension radius and thickness change amplitude of the sector, add a morphological simulation of the target breach fan to the three-dimensional river channel model.

3. A method for simulating a crevasse splay based on river channel connection relationships, characterized in that, Including: Establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; Judge whether a target breach fan to be simulated is generated according to the curvature of each control node and a preset breach fan generation threshold; Determine the connectivity relationship between the target breach fan and the river channel according to prior geological data, and determine the type of the target breach fan according to the connectivity relationship; If the target breach fan is connected to multi-period river channels, determine that the breach fan is a multi-river-channel-connected type breach fan; Simulate the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model; The method for simulating a multi-channel connected crevasse fan includes: Taking the control node at the preset crevasse position as the coordinate origin, simulate the single-channel connected crevasse fan according to the preset quantization control parameters; Judge whether there are control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan; When there are control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan, assign the single-channel connected crevasse fan as a multi-channel connected crevasse fan; When there are no control nodes of adjacent river channels within the range and extension radius of the single-channel connected crevasse fan, establish a new adjacent river channel within the single-channel connected crevasse fan according to the preset river channel generation method, and assign the single-channel connected crevasse fan as a multi-channel connected crevasse fan.

4. The method for simulating a crevasse fan based on river channel connection relationships according to claim 3, wherein, Establishing a new adjacent river channel within the single-channel connected crevasse fan according to the preset river channel generation method includes: Generate random coordinates within the single-channel connected crevasse fan and the center line of the new river channel passing through the random coordinates, and establish a new adjacent river channel based on the center line of the new river channel.

5. The method for simulating a crevasse fan based on river channel connection relationships according to any one of claims 1-3, characterized in that The preset crevasse fan generation threshold includes a minimum crevasse curvature threshold and a crevasse probability threshold; Judging whether to generate a target crevasse fan to be simulated according to the curvature of each control node and the preset crevasse fan generation threshold includes: When the curvature of the control node is greater than the minimum crevasse curvature threshold, generate a crevasse fan probability value, and judge whether the crevasse fan probability value is greater than the crevasse probability threshold; When the crevasse fan probability value is greater than the crevasse probability threshold, simulate the target crevasse fan.

6. A breach fan simulation device based on river channel connection relationship, characterized in that, Includes: An initial model establishment module, used to establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; A judgment module, used to judge whether to generate a target crevasse fan to be simulated according to the curvature of each control node and the preset crevasse fan generation threshold; A type analysis module, used to determine the connectivity relationship between the target crevasse fan and the river channel according to prior geological data, and determine the type of the target crevasse fan according to the connectivity relationship; If the target crevasse fan is connected to a single river channel, determine that the crevasse fan is a single-channel connected crevasse fan; A simulation module, used to simulate the target crevasse fan based on the type of the target crevasse fan and the three-dimensional river channel model; The method for simulating a single-channel connected target crevasse fan includes: Taking the control node at the preset crevasse position as the coordinate origin, establish a local plane coordinate system; Characterize the target crevasse fan with a sector in the local plane coordinate system, take the control node as the center of the sector, and determine the range and extension radius of the sector in the horizontal direction and the thickness change amplitude in the vertical direction according to the preset quantization control parameters; Based on the range, extension radius and thickness change amplitude of the sector, add a morphological simulation of the target crevasse fan to the three-dimensional river channel model.

7. A breach fan simulation device based on river channel connection relationship, characterized in that, Includes: An initial model establishment module, which is used to establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; A judgment module, which is used to judge whether a target breach fan to be simulated is generated according to the curvature of each control node and a preset breach fan generation threshold; A type analysis module, which is used to determine the connectivity relationship between the target breach fan and the river channel according to prior geological data, and determine the type of the target breach fan according to the connectivity relationship; If the target breach fan is not connected to the river channel, determine that the breach fan is an isolated type breach fan; A simulation module, which is used to simulate the target breach fan based on the type of the target breach fan and the three-dimensional river channel model; The method for simulating an isolated type breach fan includes: Taking the control node at the preset breach position as the coordinate origin, establish a local plane coordinate system; Determine the center movement distance based on prior geological data, and translate the position of the control node according to the center movement distance; Taking the control node after position translation as the sector center, use a sector to depict the target breach fan, and determine the range and extension radius of the sector in the horizontal direction, and the thickness change amplitude in the vertical direction according to preset quantization control parameters; Based on the range, extension radius and thickness change amplitude of the sector, add a morphological simulation of the target breach fan to the three-dimensional river channel model.

8. A breach fan simulation device based on river channel connection relationship, characterized in that Including: An initial model establishment module, which is used to establish a river channel vector line composed of a set of control nodes, calculate the curvature of each control node, and construct a three-dimensional river channel model based on the river channel vector line; A judgment module, which is used to judge whether a target breach fan to be simulated is generated according to the curvature of each control node and a preset breach fan generation threshold; A type analysis module, which is used to determine the connectivity relationship between the target breach fan and the river channel according to prior geological data, and determine the type of the target breach fan according to the connectivity relationship; If the target breach fan is connected to multi-stage river channels, determine that the breach fan is a multi-river-channel connected type breach fan; A simulation module, which is used to simulate the target breach fan based on the type of the target breach fan and the three-dimensional river channel model; The method for simulating a multi-river-channel connected type breach fan includes: Taking the control node at the preset breach position as the coordinate origin, simulate a single-river-channel connected type breach fan according to preset quantization control parameters; Judge whether there are control nodes of adjacent river channels within the range and extension radius of the single-river-channel connected type breach fan; When there are control nodes of adjacent river channels within the range and extension radius of the single-river-channel connected type breach fan, assign the single-river-channel connected type breach fan as a multi-river-channel connected type breach fan; When there are no control nodes of adjacent river channels within the range and extension radius of the single-river-channel connected type breach fan, establish a new adjacent river channel within the single-river-channel connected type breach fan according to a preset river channel generation method, and assign the single-river-channel connected type breach fan as a multi-river-channel connected type breach fan.

9. An electronic device, characterized in that, It includes a processor and a memory, and a computer program is stored on the memory. When the computer program is executed by the processor, it realizes the method for simulating a crevasse fan based on river channel connection relationships as described in any one of claims 1-4.

10. A computer-readable storage medium, characterized in that, It is used to store computer-readable programs or instructions. When the programs or instructions are executed by a processor, they can realize the steps in the method for simulating a crevasse fan based on river channel connection relationships as described in any one of claims 1-4.

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