阅读说明：本技术 一种结构和波速随机布设的三维速度地质建模方法 (Three-dimensional speed geological modeling method for random arrangement of structure and wave velocity ) 是由 蒋鹏 曹帅 杨森林 孙法合 任玉晓 高雪池 王清扬 解冬东 于 2020-10-15 设计创作，主要内容包括：本公开提供了一种结构和波速随机布设的三维速度地质建模方法,在三维空间中确定基点,根据基点建立方程确定平面层状模型,将平面层状模型的倾斜层复杂化,构建三维空间上曲面的褶皱层模型；基于三维曲面褶皱层模型,结合随机参考点的断层面,以及各点在全局坐标系中的位移,建立三维断层褶皱模型；基于三维断层褶皱模型,构造含有盐丘的速度模型,在一定深度的地质体中将盐丘向上侵入进行模拟；根据已经设定完成的层状类别,按照设定的速度范围,和每层地质之间的波速差值范围,进行随机的波速幅值,实现三维速度建模；本公开提高了深度学习方法用于地球物理反演时的模型数据量,提高了深度学习方法反演效果。(The invention provides a three-dimensional speed geological modeling method with randomly distributed structures and wave velocities, which comprises the steps of determining a base point in a three-dimensional space, establishing an equation according to the base point to determine a planar layered model, complicating a tilting layer of the planar layered model, and constructing a wrinkled layer model of a curved surface in the three-dimensional space; establishing a three-dimensional fault wrinkle model based on the three-dimensional curved surface wrinkle layer model by combining fault planes of random reference points and displacement of each point in a global coordinate system; constructing a speed model containing a salt dome based on the three-dimensional fault fold model, and simulating the upward invasion of the salt dome in a geologic body with a certain depth; according to the set layered category, according to the set speed range and the wave speed difference range between layers of geology, random wave speed amplitude values are carried out, and three-dimensional speed modeling is achieved; the method improves the model data volume when the deep learning method is used for geophysical inversion, and improves the inversion effect of the deep learning method.)

1. A three-dimensional speed geological modeling method with randomly distributed structure and wave velocity is characterized by comprising the following steps: the method comprises the following steps:

determining a base point in a three-dimensional space, establishing an equation according to the base point to determine a planar layered model, complicating a tilted layer of the planar layered model, and constructing a curved surface wrinkled layer model in the three-dimensional space;

establishing a three-dimensional fault wrinkle model based on the three-dimensional curved surface wrinkle layer model by combining fault planes of random reference points and displacement of each point in a global coordinate system;

constructing a speed model containing a salt dome based on the three-dimensional fault fold model, and simulating the upward invasion of the salt dome in a geologic body with a certain depth;

and according to the set layered type, carrying out random wave velocity amplitude values according to the set velocity range and the wave velocity difference range between each layer of geology, and realizing three-dimensional velocity modeling.

2. The three-dimensional velocity geological modeling method of random distribution of structure and wave velocity as claimed in claim 1 wherein: the specific process of determining the planar layer model according to the base point establishment equation comprises the following steps:

according to the base point (X)_ref,Y_ref,Z_ref) Establishing an equation to determine a plane layer model, and calculating a formula:

whereinRepresenting the tilt angle.

3. The three-dimensional velocity geological modeling method of random distribution of structure and wave velocity as claimed in claim 1 wherein: the specific process of complicating the inclined layers of the planar layer model includes: determining a plane layer model according to a base point establishing equation, classifying different layer models, establishing a relief function for each point on the basis of the plane model, adjusting the period and the amplitude of a trigonometric function in the relief function, then establishing an inclined term for a curved surface, further complicating an inclined layer, and establishing a three-dimensional curved surface corrugated layer model.

4. A three-dimensional velocity geological modeling method of random placement of structure and wave velocity as defined in claim 3 wherein: the specific process comprises the following steps:

establishing a fold model based on the plane layer model, and calculating a formula:

wherein T is_i A_iRespectively representing period and amplitude, and randomly selecting values;

the formula of the inclination term aiming at the curved surface is established as follows: d (X, Y) ═ b₁(X-X_ref)+b₂(Y-Y_ref)

Wherein X_ref Y_refAs coordinates of the base point, b₁ b₂The value of (2) is randomly selected.

5. The three-dimensional velocity geological modeling method of random distribution of structure and wave velocity as claimed in claim 1 wherein: the specific process for establishing the three-dimensional fault fold model comprises the following steps:

the formula for adding faults to the wrinkle model is:

c₁(X-X_ref)+c₂(Y-Y_ref)+c₃(Z-Z_ref)＝0

wherein c is₁ c₂ c₃Is obtained by rotating matrix calculation:rotation matrixWherein phi theta is randomly in [0,2 pi ]]Medium value for random d_x d_yIn global coordinates D_X D_Y D_ZComprises the following steps:

6. the three-dimensional velocity geological modeling method of random distribution of structure and wave velocity as claimed in claim 1 wherein: the concrete process of simulating the upward invasion of salt dune in geologic body with certain depth includes: the invasion is fitted through a two-dimensional Gaussian function, the height of vertical invasion is defined by amplitude, the size is determined by variance, the trend is determined by a clockwise rotation angle, an influence area with a certain thickness is arranged, the maximum invasion height is on the bottom layer, the influence is smaller when the maximum invasion height is closer to the earth surface in the influence area, the layer on the influence area is kept unchanged, and the addition of a salt dome is completed.

7. The method for three-dimensional geological modeling of velocity of structures and waves randomly laid out as claimed in claim 6, wherein: the formula for establishing the salt dome is as follows:

G(X,Y)＝Aexp(-(d₁(X-X_ref)²+d₃(Y-Y_ref)²+2d₂(X-X_ref)(Y-Y_ref)))

wherein

A represents the height of a vertically invading salt dome, which has a size ofControl, the region of influence of the salt dome is set to [ A ]_max+5,A_max+15]Wherein A is_maxRepresenting the maximum invasion height, the shallower the layer in the affected area, the smaller the amplitude a of the corresponding gaussian function, and the formation above the affected area remains unchanged.

8. The three-dimensional velocity geological modeling method of random distribution of structure and wave velocity as claimed in claim 1 wherein: the specific process of carrying out random wave velocity amplitude and realizing three-dimensional velocity modeling comprises the following steps:

randomly generating a vector V' of n +1 elements according to the number n of layers;

accumulating the vector V' to generate a vector V₁；

Taking a random speed reference value M, wherein M belongs to [ x ]₁,x₂]，x₁,x₂Upper and lower speed bounds;

get V₁Last element v_end；

The velocity is assigned as V ═ V (V)₁/v_end)·M；

For salt dome to randomly take velocity V_{Salt dome}，V_{Salt dome}∈[M,M+Δv]Where Δ v is a random incremental velocity value.

9. A computer-readable storage medium characterized by: stored with instructions adapted to be loaded by a processor of a terminal device and to perform a method of three-dimensional velocity geological modeling of a stochastic layout of structure and wave velocity according to any of claims 1-8.

10. A terminal device is characterized in that: the system comprises a processor and a computer readable storage medium, wherein the processor is used for realizing instructions; a computer readable storage medium storing instructions adapted to be loaded by a processor and to perform a method of three-dimensional velocity geological modeling of a stochastic layout of structures and wave velocities as claimed in any of claims 1 to 8.

Technical Field

The disclosure belongs to the technical field of geophysical exploration, and relates to a three-dimensional speed geological modeling method for randomly distributing structures and wave velocities.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The seismic method is one of the most common geophysical exploration methods, is widely applied to petroleum exploration, coal fields, metal mineral deposit exploration and the like, and has wide application prospect. The main principle of the seismic method is based on wave field propagation, a plurality of detectors are arranged on the ground, a wave field is generated by exciting an artificial seismic source for a plurality of times and is propagated in an underground medium, when the wave impedance of the underground medium changes and is reflected or refracted to return to the ground, the detectors on the ground record vibration information propagated to the ground, and seismic data are processed by an imaging or inversion method to obtain distribution information of the underground medium. The inversion method can improve seismic resolution, obtain more accurate underground structure information, improve evaluation capability of underground media, and gradually become an unavailable part in seismic data processing.

According to the knowledge of the inventor, the seismic data inversion method based on the deep learning method is a popular method at present and achieves a good effect. Seismic data inversion based on a deep learning method is an algorithm based on data driving, and essentially a mapping relation from a geological model to observed data is established through a large amount of data, and if the large amount of data cannot be obtained, the performance of the algorithm is greatly reduced. Therefore, the method puts high requirements on data acquisition. A reasonable model is established, data are obtained through forward modeling, which is a commonly used method at present, the existing speed modeling method mainly adopts a manual model establishing method and a two-dimensional batch speed modeling method, and the methods have the following problems:

first, the modeling cost is too high;

in a traditional modeling approach, building a complex velocity model usually relies on expert knowledge of geological interpretation of seismic survey data for a certain subsurface region of the earth, and a velocity model for that region is then built. During the model construction process, a large amount of labeled data sets cannot be used for training the deep learning inversion network due to the large manual workload and cost.

Secondly, the model complexity is low;

the existing batch speed modeling method mainly establishes a two-dimensional speed model, mainly establishes a two-dimensional simple lamellar or fault model, is not consistent with the actual geological condition, has too low model complexity, does not establish a scheme of a rock dune model, is not enough to simulate the actual geological condition, and directly causes that a neural network obtained by using a deep learning method has poor effect when facing a more complex actual model.

The main difficulties in implementing the velocity modeling are the following two aspects:

1) reasonable algorithms and functions are required to randomly establish a reasonable speed model;

the geological model is formed by geological motion, has great randomness and regional property, and simultaneously has geological history information, so that the speed model which can simulate real geological information and is generated by a function needs to meet the general rule of the stratum and has enough randomness to avoid model repetition, and great difficulty exists.

2) On the premise of ensuring the complexity of the model, the rapid modeling is difficult to realize;

when the model is established, parameters need to be randomly selected, a speed model is generated in a reasonable range, high requirements on parameter selection are provided by ensuring the complexity of the model, and the difficulty in further realizing rapid random speed modeling is further increased.

Disclosure of Invention

The three-dimensional speed geological modeling method aims at solving the problem that a deep neural network lacks a training data set, and randomly establishes three-dimensional speed models in batch to solve the blank in the aspect of establishing the three-dimensional speed models at present. The data set scale is improved, and the inversion effect of the deep learning method is effectively improved.

According to some embodiments, the following technical scheme is adopted in the disclosure:

a three-dimensional speed geological modeling method for randomly distributing structure and wave velocity comprises the following steps:

determining a base point in a three-dimensional space, establishing an equation according to the base point to determine a planar layered model, complicating a tilted layer of the planar layered model, and constructing a curved surface wrinkled layer model in the three-dimensional space;

establishing a three-dimensional fault wrinkle model based on the three-dimensional curved surface wrinkle layer model by combining fault planes of random reference points and displacement of each point in a global coordinate system;

constructing a speed model containing a salt dome based on the three-dimensional fault fold model, and simulating the upward invasion of the salt dome in a geologic body with a certain depth;

and according to the set layered type, carrying out random wave velocity amplitude values according to the set velocity range and the wave velocity difference range between each layer of geology, and realizing three-dimensional velocity modeling.

As an alternative embodiment, the specific process of determining the planar layer model according to the base point establishment equation includes:

according to the base point (X)_ref,Y_ref,Z_ref) Establishing an equation to determine a plane layer model, and calculating a formula:

whereinRepresenting the tilt angle.

As an alternative embodiment, the specific process of complicating the inclined layers of the planar layer model includes: determining a plane layer model according to a base point establishing equation, classifying different layer models, establishing a relief function for each point on the basis of the plane model, adjusting the period and the amplitude of a trigonometric function in the relief function, then establishing an inclined term for a curved surface, further complicating an inclined layer, and establishing a three-dimensional curved surface corrugated layer model.

As a further limitation, the specific process comprises:

establishing a fold model based on the plane layer model, and calculating a formula:

wherein T is_i A_iRespectively representing period and amplitude, and randomly selecting values;

the formula of the inclination term aiming at the curved surface is established as follows: d (X, Y) ═ b₁(X-X_ref)+b₂(Y-Y_ref)

Wherein X_ref Y_refAs coordinates of the base point, b₁ b₂The value of (2) is randomly selected.

As an alternative embodiment, the specific process of establishing the three-dimensional fault wrinkle model includes:

the formula for adding faults to the wrinkle model is:

c₁(X-X_ref)+c₂(Y-Y_ref)+c₃(Z-Z_ref)＝0

wherein c is₁ c₂ c₃Is obtained by rotating matrix calculation:rotation matrixWherein phi theta are all random in[0,2π]Medium value for random d_x d_yIn global coordinates D_X D_Y D_ZIs provided with

As an alternative embodiment, the specific process of simulating the intrusion of salt domes upwards in a geologic body of a certain depth comprises: the invasion is fitted through a two-dimensional Gaussian function, the height of vertical invasion is defined by amplitude, the size is determined by variance, the trend is determined by a clockwise rotation angle, an influence area with a certain thickness is arranged, the maximum invasion height is on the bottom layer, the influence is smaller when the maximum invasion height is closer to the earth surface in the influence area, the layer on the influence area is kept unchanged, and the addition of a salt dome is completed.

By way of further limitation, the formula for establishing a salt dome is:

G(X,Y)＝Aexp(-(d₁(X-X_ref)²+d₃(Y-Y_ref)²+2d₂(X-X_ref)(Y-Y_ref)))

wherein

A represents the height of a vertically invading salt dome, which has a size ofControl, the region of influence of the salt dome is set to [ A ]_max+5,A_max+15]Wherein A is_maxRepresenting the maximum invasion height, the shallower the layer in the affected area, the smaller the amplitude a of the corresponding gaussian function, and the formation above the affected area remains unchanged.

As an alternative embodiment, random wave velocity amplitude is performed, and the specific process for realizing three-dimensional velocity modeling includes:

randomly generating a vector V' of n +1 elements according to the number n of layers;

accumulating the vector V' to generate a vector V₁；

Taking a random speed reference value M, wherein M belongs to [ x ]₁,x₂]，x₁,x₂Upper and lower speed bounds;

get V₁Last element v_end；

The velocity is assigned as V ═ V (V)₁/v_end)·M；

For salt dome to randomly take velocity V_{Salt dome}，V_{Salt dome}∈[M,M+Δv]Where Δ v is a random incremental velocity value.

A computer readable storage medium having stored therein a plurality of instructions adapted to be loaded by a processor of a terminal device and to execute said method of three-dimensional velocity geological modeling of a stochastic layout of structure and wave velocity.

A terminal device comprising a processor and a computer readable storage medium, the processor being configured to implement instructions; the computer readable storage medium stores instructions adapted to be loaded by a processor and to perform the method for three-dimensional velocity geological modeling of a stochastic layout of structure and wave velocity.

Compared with the prior art, the beneficial effect of this disclosure is:

the method aims at three-dimensional speed modeling in geological modeling, and processes the following steps: in consideration of the fact that no three-dimensional speed modeling method is provided at present, the three-dimensional speed modeling method is provided, and a speed model conforming to the real geology is generated through function simulation.

Meanwhile, the batch modeling method is also provided, and in consideration of the problem that the original geological modeling method cannot be used for batch modeling, the MATLAB software is used for writing the algorithm, so that the modeling speed is greatly increased, the available batch modeling method is formed, the data set for performing three-dimensional speed inversion by using the deep learning method is greatly increased, and the accuracy of performing speed inversion by using the deep learning method can be effectively improved.

The method aims at the problem that salt dome simulation is not carried out in the traditional modeling, function fitting aiming at the salt dome is carried out, the concept of an influence layer is provided, and the salt dome in deep geology is reasonably simulated, so that the modeling result is closer to the real geology.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure and are not to limit the disclosure.

FIG. 1 is a flow chart of the method of the present embodiment;

FIG. 2 is a flow chart of the modeling of the laminar fold model according to the present embodiment;

FIG. 3 is a flowchart of a fault model modeling of the present embodiment;

FIG. 4 is a flow chart of salt dome modeling in the present example;

FIGS. 5(a) - (c) are schematic diagrams of a lamellar model, a fault model and a salt dome model, respectively.

The specific implementation mode is as follows:

the present disclosure is further described with reference to the following drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The three-dimensional velocity modeling method, as shown in fig. 1, includes the following steps:

step S1, determining a base point in a three-dimensional space, determining a planar layered model according to a base point establishing equation, establishing a relief function for each point on the basis of the planar model, and further establishing a complex inclined layer by adjusting the period and amplitude of a trigonometric function in the relief function and then establishing an inclined term for the curved surface, and establishing a corrugated layer model of the curved surface in the three-dimensional space;

the model size of this example is nx × ny × nz, and an x layer layered model is generated.

In the present example, based on the base point (X)_ref,Y_ref,Z_ref) Establishing an equation to determine a plane layer model, and calculating a formula:

in this example, a wrinkle model is established based on a surface layered model, and a calculation formula is as follows:

the formula of the tilt term for the curved surface is established in this example as: d (X, Y) ═ b₁(X-X_ref)+b₂(Y-Y_ref)

Step S2, based on the established three-dimensional curved surface fold layer model, establishing an equation through a determined random reference point, determining a fault plane passing through the reference point, determining the displacement of each point in a global coordinate system through a rotation matrix, and establishing a three-dimensional fault fold model;

the formula for establishing the fault model in the embodiment is as follows:

c₁(X-X_ref)+c₂(Y-Y_ref)+c₃(Z-Z_ref)＝0

wherein c is₁ c₂ c₃Is obtained by rotating matrix calculation:rotation matrixWherein phi theta is randomly in [0,2 pi ]]Middle value

Step S3, constructing a velocity model containing salt dome based on the fold model, and geologic body at a certain depthIn the method, the intrusion of the salt dome is simulated, the intrusion is fitted by a two-dimensional Gaussian function, the height of vertical intrusion is defined by amplitude, and the size is defined by variance sigma_x，σ_yAnd determining that the trend is determined by the clockwise rotation angle theta, and because the influence of the salt dome on the upper layer is small, an influence area with a certain thickness is arranged, the maximum invasion height is at the bottom layer, the influence is smaller when the influence area is closer to the ground surface, and the layer on the influence area is kept unchanged, so that the salt dome is added.

The formula for creating the salt dome in this example is:

G(X,Y)＝Aexp(-(d₁(X-X_ref)²+d₃(Y-Y_ref)²+2d₂(X-X_ref)(Y-Y_ref)))

wherein

A represents the height of a vertically invading salt dome, which has a size ofControl, the region of influence of the salt dome is set to [ A ]_max+5,A_max+15]Wherein A is_maxRepresenting the maximum invasion height, the shallower the layer in the affected area, the smaller the amplitude a of the corresponding gaussian function, and the formation above the affected area remains unchanged.

Step S4, based on the established model, the wave velocity is randomly assigned to each layer

The wave velocity assignment process is as follows:

1. randomly generating vector V 'of n +1 elements according to the number n of layers'

2. Accumulating the vector V' to generate a vector V₁

3. Taking a random speed reference value M, wherein M belongs to [ x ]₁,x₂](x₁,x₂For the upper and lower speed bounds, in this example, take M e [2000M/s,4000M/s])

4. Get V₁Last element v_end

5. The velocity is assigned as V ═ V (V)₁/v_end)·M

6. To pairRandom speed V of salt dome_{Salt dome}，V_{Salt dome}∈[M,M+Δv]Wherein Δ v is a random increasing speed value, in this example, 300-500 m/s.

The main network parameters and hardware conditions in this embodiment are: the calculation was carried out using AMD R5-4600u CPU. Algorithm writing calculations were performed using MATLAB.

The following product examples are also provided:

a computer readable storage medium having stored therein a plurality of instructions adapted to be loaded by a processor of a terminal device and to execute said method of three-dimensional velocity geological modeling of a stochastic layout of structure and wave velocity.

A terminal device comprising a processor and a computer readable storage medium, the processor being configured to implement instructions; the computer readable storage medium stores instructions adapted to be loaded by a processor and to perform the method for three-dimensional velocity geological modeling of a stochastic layout of structure and wave velocity.

As will be appreciated by one skilled in the art, embodiments of the present disclosure may be provided as a method, system, or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and so forth) having computer-usable program code embodied therein.

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure, and various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Although the present disclosure has been described with reference to specific embodiments, it should be understood that the scope of the present disclosure is not limited thereto, and those skilled in the art will appreciate that various modifications and changes can be made without departing from the spirit and scope of the present disclosure.