Phase-constrained sandstone thickness earthquake prediction method, system and equipment based on multi-point geostatistics and medium

Abstract

The invention relates to a facies-constrained sandstone thickness earthquake prediction method, system and device based on multipoint geostatistics and a medium. The method comprises the following steps: establishing a seismic facies interpretation chart of different lithology combinations of well point positions in a known three-dimensional research area; carrying out seismic facies interpretation of the to-be-researched two-dimensional survey line in combination with the seismic facies interpretation charts of different lithologic combinations in the known three-dimensional research area, and determining different lithologic combinations and sandstone thickness distribution characteristics on the to-be-researched two-dimensional survey line; carrying out two-dimensional area sedimentary facies prediction based on multipoint geostatistics by taking to-be-researched two-dimensional survey line seismic facies interpretation and drilling information as constraints; and under the constraint of a prediction result of the sedimentary facies of the to-be-researched two-dimensional region, realizing sandstone prediction of the to-be-researched two-dimensional region by utilizing a two-point geostatistics method in combination with the thickness information of the drilled sandstone and the known information such as a sandstone thickness variation function of the three-dimensional research region. The method can be widely applied to the technical field of seismic reservoir prediction.

Description

Technical Field

[0001] The invention relates to a phase-constrained sandstone thickness seismic prediction method, system, equipment and medium based on multi-point geostatistics, belonging to the technical field of seismic reservoir prediction. Background Art

[0002] Compared with three-dimensional seismic areas, the distance intervals between survey lines in two-dimensional seismic areas are usually larger and the density is uneven. It is necessary to solve the problem of how to use the survey lines in two-dimensional seismic areas to realize the plane prediction of the target layer sandstone from "line" to "surface".

[0003] Among the existing methods, the sandstone thickness prediction is mainly achieved by combining two-dimensional seismic attributes with plane interpolation methods. The plane prediction results are greatly affected by the interpolation method and the two-dimensional survey line interval, and have strong multi-solution. The prediction results usually circle around the seismic survey lines, and the density of the survey lines also directly affects the plane change characteristics of the sandstone thickness interpolation results, resulting in the prediction results being unable to reflect the changes in the sand body itself, which is inconsistent with the geological laws. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a phase-constrained sandstone thickness seismic prediction method, system, equipment and medium based on multi-point geostatistics. This method realizes sandstone thickness prediction based on multi-point geostatistics and phase constraints, which can effectively improve the prediction accuracy.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a method for seismic prediction of sandstone thickness based on multi-point geostatistics, comprising the following steps:

[0007] Establish seismic facies interpretation charts of different lithology combinations at known well point locations in the three-dimensional study area;

[0008] Combined with the seismic facies interpretation plates of different lithology combinations in the known three-dimensional study area, the seismic facies interpretation of the survey line in the two-dimensional area to be studied is carried out to determine the distribution characteristics of different lithology combinations and sandstone thickness on the survey line in the two-dimensional area to be studied;

[0009] The 2D area sedimentary facies prediction is carried out based on multi-point geostatistics, with the seismic facies interpretation and drilling information of the 2D area to be studied as constraints;

[0010] Under the constraints of the sedimentary facies prediction results of the two-dimensional area to be studied, the sandstone thickness in the two-dimensional area to be studied is predicted by using the two-point geostatistical method, combined with the sandstone thickness information of the drilled wells and the variogram information of the sandstone thickness in the known three-dimensional study area.

[0011] Further, the establishment of seismic phase interpretation charts of different lithology combinations at well point locations in a known three-dimensional study area includes the following steps:

[0012] The seismic phase characteristics of different lithology combinations at the well point locations in the known three-dimensional study area are determined by well-seismic calibration;

[0013] The seismic facies characteristics of different lithology combinations determined were verified through forward modeling;

[0014] Based on the verified seismic facies characteristics of different lithology combinations, seismic facies interpretation maps of different lithology combinations are established.

[0015] Furthermore, the two-dimensional area sedimentary facies prediction is carried out based on multi-point geostatistics with the seismic facies interpretation of the survey line and drilling information of the two-dimensional area to be studied as constraints, including:

[0016] The sedimentary facies study of the known three-dimensional study area is used as the training image;

[0017] Build a pattern library based on training images;

[0018] Based on the constructed model library, multi-point geostatistical phase simulation is carried out with the seismic phase interpretation of the survey line and drilling information of the two-dimensional area to be studied as constraints to realize the sedimentary phase prediction of the two-dimensional area to be studied.

[0019] Further, the constructing of a pattern library based on the training image includes:

[0020] The size of the scanning window is determined according to the scale of different sedimentary facies types. The scanning window is used to identify the probability distribution of all possible attribute combinations from the training image to obtain a pattern library.

[0021] Furthermore, for the predicted position u in the two-dimensional area to be studied, the sedimentary phase prediction result is expressed as P*, then:

[0022] p * (u) = argmax p∈L d(u,p)

[0023] Among them, d is a measure of the similarity between patterns.

[0024] Furthermore, the plane prediction result of the sandstone thickness in the two-dimensional area to be studied is expressed as:

[0025]

[0026] Where Z*(u) is the thickness of sandstone at the position u to be predicted, w n is the well data weight, Z n is the sandstone thickness at the well point, w k is the earthquake attribute weight, Y k is the seismic attribute related to the sandstone thickness of the drilling, N is the number of drilling wells, and K is the number of 2D seismic lines.

[0027] In a second aspect, the present invention provides a facies-constrained sandstone thickness seismic prediction system based on multi-point geostatistics, comprising:

[0028] The "point" phase determination module is used to establish seismic phase interpretation charts of different lithology combinations at well point locations in a known three-dimensional study area;

[0029] The "Line" phase determination module is used to combine the seismic phase interpretation plates of different lithology combinations in the known three-dimensional study area to carry out seismic phase interpretation of the two-dimensional survey line to be studied, and determine the distribution characteristics of different lithology combinations and sandstone thickness on the two-dimensional survey line to be studied;

[0030] The "surface" facies determination module is used to carry out sedimentary facies prediction in a two-dimensional area based on multi-point geostatistics, with the seismic facies interpretation of the two-dimensional survey line to be studied and the drilling information as constraints;

[0031] The phase-constrained sandstone thickness simulation module is used to realize the sandstone prediction of the two-dimensional area to be studied by combining the drilled sandstone thickness information and the known three-dimensional sandstone thickness variation function under the constraint of the sedimentary phase prediction results of the two-dimensional area to be studied, using the two-point geostatistical method.

[0032] Furthermore, the "surface" phasing module includes:

[0033] A training data acquisition module is used to study the sedimentary facies of a known three-dimensional study area as a training image;

[0034] A pattern library building module is used to build a pattern library based on training images;

[0035] The 2D sedimentary facies prediction module is used to carry out multi-point geostatistical facies simulation based on the constructed model library, with the 2D survey line seismic facies interpretation and drilling information as constraints, and thus realize the sedimentary facies prediction of the 2D area to be studied.

[0036] In a third aspect, the present invention provides a computer-readable storage medium storing one or more programs, wherein the one or more programs include instructions, which, when executed by a computing device, cause the computing device to perform any method.

[0037] In a fourth aspect, the present invention provides a computing device, comprising: one or more processors and a memory, wherein the memory stores one or more programs and is configured to be executed by the one or more processors, and the one or more programs include instructions for executing any method.

[0038] The present invention adopts the above technical solution, which has the following advantages:

[0039] The phase-constrained sandstone prediction method based on multi-point geostatistics provided by the present invention can, on the one hand, effectively combine the geological understanding formed in three-dimensional mature exploration areas, and on the other hand, the prediction results are consistent with the seismic phases and drilling results in the two-dimensional area, effectively avoiding the problem of unreasonable sandstone prediction results in two-dimensional seismic areas due to sparse seismic data.

[0040] Therefore, the present invention can be widely applied to the technical field of seismic reservoir prediction. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components. In the accompanying drawings:

[0042] Figure 1 is a flow chart of a phase-constrained sandstone thickness seismic prediction method provided by an embodiment of the present invention;

[0043] Figure 2 is a location map of a research area provided by an embodiment of the present invention;

[0044] Figure 3 It is a seismic phase interpretation plate of the study area provided by an embodiment of the present invention;

[0045] Figure 4 It is a seismic phase interpretation profile of a two-dimensional survey line B in the study area provided by an embodiment of the present invention;

[0046] Figure 5 is the sedimentary facies prediction result of the study area provided by the embodiment of the present invention;

[0047] Figure 6 It is the statistical result of the proportion of different types of sedimentary phases in the study area provided by the embodiment of the present invention;

[0048] Figure 7 This is the prediction result of the sandstone thickness of the target layer in the study area provided by the embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0050] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0051] In some embodiments of the present invention, a phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics is provided. The method includes: "point" phase determination, "line" phase determination, "surface" phase determination and phase-constrained sandstone thickness simulation, using the sedimentary phase research results of the known three-dimensional study area to predict the sandstone thickness in the two-dimensional area, and the prediction result is consistent with the well point and conforms to the geological understanding of the three-dimensional mature exploration area.

[0052] Correspondingly, in other embodiments of the present invention, a phase-constrained sandstone thickness seismic prediction system, equipment and medium based on multi-point geostatistics are provided.

[0053] Example 1

[0054] like Figure 1 As shown, the present invention provides a phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics, which includes the following steps:

[0055] 1) “Point” facies determination: Establish seismic facies interpretation charts of different lithology combinations at the well point locations in the known three-dimensional study area;

[0056] 2) “Line” facies determination: Combined with the seismic facies interpretation plates of different lithology combinations in the known three-dimensional study area, the seismic facies interpretation of the two-dimensional survey line to be studied is carried out to determine the distribution characteristics of different lithology combinations and sandstone thickness on the two-dimensional survey line to be studied;

[0057] 3) “Surface” facies determination: Seismic facies interpretation of the 2D survey line to be studied and drilling information are used as constraints to carry out 2D area sedimentary facies prediction based on multi-point geostatistics;

[0058] 4) Phase-constrained sandstone thickness simulation: Under the constraints of the sedimentary phase prediction results of the two-dimensional area to be studied, combined with the drilled sandstone thickness information and the known three-dimensional sandstone thickness variation function of the study area, the two-point geostatistical method is used to realize the sandstone prediction of the two-dimensional area to be studied.

[0059] Furthermore, in the above step 1), establishing a seismic facies interpretation chart of different lithology combinations at the well point locations in the study area includes the following steps:

[0060] 1.1) Determine the seismic phase characteristics of different lithology combinations at the well location in the study area through well-seismic calibration;

[0061] 1.2) Verify the seismic phase characteristics of different lithology combinations through forward modeling;

[0062] 1.3) Based on the verified seismic facies characteristics of different lithological combinations, establish seismic facies interpretation maps of different lithological combinations.

[0063] Furthermore, the above step 3) includes the following steps:

[0064] 3.1) The sedimentary facies of the known three-dimensional study area is used as a training image, wherein the training image contains the plane proportion, direction, curvature, etc. of the sedimentary facies.

[0065] 3.2) Construct a pattern library L based on the training images.

[0066] Specifically, the method for constructing the pattern library L includes: determining the size of the scanning window according to the scale of different sedimentary phase types, and using the scanning window to identify the probability distribution of all possible attribute combinations from the training image, that is, the pattern library L contains all pattern combinations scanned and extracted from the training image and the occurrence probability of different patterns.

[0067] 3.3) Based on the constructed model library L, multi-point geostatistical facies simulation is carried out with the seismic facies interpretation of the 2D survey line and drilling information as constraints, thereby realizing the sedimentary facies prediction of the 2D area to be studied.

[0068] In this embodiment, the sedimentary facies prediction results of the two-dimensional area to be studied are consistent with the seismic facies interpretation results at the well points, reflecting the understanding of seismic facies research in mature exploration areas. The plane phase diagram has a natural transition with the known three-dimensional study area, and the plane phase ratio is reasonable.

[0069] For the predicted position u, the predicted sedimentary phase result of the position can be expressed as P * ,but:

[0070] p * (u) = argmax p∈L d(u,p)

[0071] Among them, d is a measure of the similarity between patterns.

[0072] Furthermore, in the above step 4), the calculation formula for the plane prediction result of the sandstone thickness in the two-dimensional area to be studied is expressed as:

[0073]

[0074] Where Z*(u) is the thickness of sandstone at the position u to be predicted, w n is the well data weight, Z n is the sandstone thickness at the well point, w k is the earthquake attribute weight, Y kis the seismic attribute related to the sandstone thickness of the drilling, N is the number of drilling wells, and K is the number of 2D seismic lines.

[0075] Example 2

[0076] This embodiment takes an existing study area as an example to further introduce the phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics provided by the present invention.

[0077] like Figure 2 As shown, the study area A is the 3D seismic coverage area with an area of ​​300km 2 27 wells have been drilled in the area. Study area B is located to the east of area A and is a two-dimensional seismic area with an area of ​​130km 2 , including 13 two-dimensional survey lines, and 2 wells have been drilled in the area. By conducting comparative analysis of the three-dimensional seismic profiles of Area A and the two-dimensional seismic profiles of Area B, the seismic events of the two work areas can be continuously tracked and interpreted, and the seismic reflection characteristics are similar and comparable. Therefore, this embodiment combines the three-dimensional seismic geological knowledge of Area A to carry out seismic prediction of sandstone distribution in Area B. The specific implementation process is as follows:

[0078] 1) “Point” phasing

[0079] The seismic phase characteristics of different lithology combinations at the well points are determined through well-seismic calibration, and the results are verified through forward simulation, and then the seismic phase interpretation plates of different lithology combinations are established.

[0080] like Figure 3 As shown, there are three types of lithofacies combinations developed in the target layer of the study area. The first is a single sand body or multiple sand body combination type developed in the main part of the distributary channel. This type of sand body is relatively thick, with an overall thickness of more than 5m. The original seismic waveform and forward modeling results show the reflection characteristics of medium-strong peaks and medium-strong troughs. The second is a combination of multiple thin-layer sandstones and thick-layer mudstones developed on the side edge of the distributary channel. This type of sand body is relatively thin, with an overall thickness of 3m-5m. The original seismic waveform and forward modeling results show the composite reflection characteristics of weak peaks and troughs. The third is a type of thin sandstone or undeveloped sandstone developed between distributary channels. This type of sand body is thin, with an overall thickness of less than 3m. The original seismic waveform and forward modeling results show the reflection characteristics of weak peaks and weak troughs.

[0081] 2) “Line” phasing

[0082] Combined with the seismic facies interpretation plate of the study area, seismic facies interpretation of the two-dimensional seismic survey line was carried out to determine the spatial distribution characteristics of different types of lithofacies in the study area B along the two-dimensional survey line.

[0083] like Figure 4As shown in the figure, based on the seismic response characteristics of different types of lithofacies in the study area, the seismic phase interpretation of 13 2D seismic lines in the study area B was completed, and the distribution characteristics of 2D survey lines of different seismic phases in the target layer were obtained, thereby clarifying the distribution characteristics of 2D survey lines of different sedimentary phases such as the main body of the distributary channel, the lateral edge of the channel and between the channels.

[0084] 3) “face” phasing

[0085] Multi-point geostatistics is a method used to simulate complex geological bodies. Unlike the traditional two-point geostatistics method, the multi-point geostatistics method can capture and reproduce the complex spatial patterns in the geological structure, and thus effectively characterize the heterogeneous characteristics of the geological body. The core idea is to use known geological data to define the spatial distribution pattern of the geological body, and to generate new data with similar geological structures by analyzing and training the spatial relationship between multiple points in the known geological data, while maintaining consistency with observation data such as drilling and seismic data.

[0086] The sedimentary phase plane prediction of target layer B in the study area was carried out based on multi-point geostatistical methods.

[0087] First, the sedimentary facies research results of the mature exploration area in the study area A are used as the training statistical sample Tl. Tl contains information such as the plane proportion, direction and curvature of the sedimentary facies that can describe the sedimentary facies characteristics of the study area B.

[0088] Secondly, the size of the scanning window is determined according to the scale of different sedimentary facies types, and the probability distribution of all possible attribute combinations is identified from Tl using the scanning window. By scanning the sedimentary facies data of the study area A, a pattern library L is constructed, which contains all the pattern combinations extracted from Tl and the occurrence probability of different patterns.

[0089] Finally, based on the constructed model library L and under the constraints of the seismic facies interpretation results of the drilled wells and two-dimensional survey lines in the study area B, a planar prediction of sedimentary facies in the two-dimensional area was carried out. The well points were consistent with the logging interpretation results, and the seismic facies interpretation results were referenced between the lines, reflecting the understanding of seismic facies research in mature exploration areas.

[0090] like Figure 5 As shown in the figure, it is the simulation result of sedimentary phase in study area B. It can be seen from the figure that the plane phase diagram of study area B has a reasonable geological morphology, and has a natural transition with the plane phase diagram of study area A, without a "hard boundary" caused by different data levels.

[0091] like Figure 6The figure shows the statistical histogram of the proportion of different types of sedimentary phases in the 3D seismic study area A and the 2D seismic study area B. The statistical results show that the two have similar statistical characteristics, indicating that the sedimentary characteristics in the study area B reasonably reflect the geological characteristics described by the sedimentary phase data of the study area A. The analysis of the seismic phase interpretation results of the drilled wells and the 2D survey lines in the study area B shows that the planar sedimentary phase prediction results are consistent with the drilling, and the planar variation law of the sedimentary phase is consistent with the seismic phase interpretation results of the 2D survey lines. Therefore, the sedimentary phase prediction results of this method are consistent with the existing geological understanding of the mature 3D seismic exploration area and meet the drilling and seismic phase interpretation results of the 2D seismic work area, and can accurately reflect the sedimentary phase characteristics of the 2D seismic study area B.

[0092] 4) Prediction of sandstone thickness in phase-constrained two-dimensional areas

[0093] The plane prediction results of sedimentary phase B in the study area are used as thickness trends. Combined with the information of drilled wells and seismic attributes of two-dimensional survey lines, the two-point geostatistical method is used to carry out plane prediction of sandstone thickness in the two-dimensional area.

[0094] like Figure 6 As shown in the figure, the prediction results are consistent with the well points at a rate of 72%, which is in good agreement with the geological understanding of the three-dimensional mature exploration area and can provide guidance for the deployment of well locations in the study area B.

[0095] Example 3

[0096] The above-mentioned embodiment 1 provides a phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics. Correspondingly, this embodiment provides a phase-constrained sandstone thickness seismic prediction system based on multi-point geostatistics. The system provided in this embodiment can implement the phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics of embodiment 1, and the system can be implemented by software, hardware, or a combination of software and hardware. For example, the system may include integrated or separate functional modules or functional units to execute the corresponding steps in each method of embodiment 1. Since the system of this embodiment is basically similar to the method embodiment, the process described in this embodiment is relatively simple, and the relevant parts can refer to the partial description of embodiment 1. The embodiment of the system provided in this embodiment is only schematic.

[0097] The facies-constrained sandstone thickness seismic prediction system provided in this embodiment based on multi-point geostatistics includes:

[0098] The "point" phase determination module is used to establish seismic phase interpretation charts of different lithology combinations at well point locations in a known three-dimensional study area;

[0099] The "Line" phase determination module is used to combine the seismic phase interpretation plates of different lithology combinations in the known three-dimensional study area to carry out seismic phase interpretation of the two-dimensional survey line to be studied, and determine the distribution characteristics of different lithology combinations and sandstone thickness on the two-dimensional survey line to be studied;

[0100] The "surface" facies determination module is used to carry out sedimentary facies prediction in a two-dimensional area based on multi-point geostatistics, with the seismic facies interpretation of the two-dimensional survey line to be studied and the drilling information as constraints;

[0101] The phase-constrained sandstone thickness simulation module is used to realize the sandstone prediction of the two-dimensional area to be studied by combining the drilled sandstone thickness information and the known three-dimensional sandstone thickness variation function under the constraint of the sedimentary phase prediction results of the two-dimensional area to be studied, using the two-point geostatistical method.

[0102] Further, the "face" phasing module includes:

[0103] A training data acquisition module is used to study the sedimentary facies of a known three-dimensional study area as a training image;

[0104] A pattern library building module is used to build a pattern library based on training images;

[0105] The 2D sedimentary facies prediction module is used to carry out multi-point geostatistical facies simulation based on the constructed model library, with the 2D survey line seismic facies interpretation and drilling information as constraints, and thus realize the sedimentary facies prediction of the 2D area to be studied.

[0106] Example 4

[0107] This embodiment provides a processing device corresponding to the phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics provided in this embodiment 1. The processing device can be a processing device for a client, such as a mobile phone, a laptop computer, a tablet computer, a desktop computer, etc., to execute the method of embodiment 1.

[0108] The processing device includes a processor, a memory, a communication interface and a bus, and the processor, the memory and the communication interface are connected through the bus to complete mutual communication. The memory stores a computer program that can be run on the processor, and the processor executes the multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method provided in Example 1 when running the computer program.

[0109] Preferably, the memory may be a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory.

[0110] Preferably, the processor may be a central processing unit (CPU), a digital signal processor (DSP) or other general-purpose processors of various types, which are not limited here.

[0111] Example 5

[0112] The phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics of this embodiment 1 can be specifically implemented as a computer program product, which may include a computer-readable storage medium carrying computer-readable program instructions for executing the phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics described in this embodiment 1.

[0113] Computer readable storage media can be tangible devices that hold and store instructions used by instruction execution devices. Computer readable storage media can be, for example, but not limited to, electronic storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any combination thereof.

[0114] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0115] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0116] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A phase-constrained sandstone thickness seismic prediction method based on multi-point geostatistics, characterized in that: The following steps are involved: Establish seismic facies interpretation charts of different lithology combinations at known well point locations in the three-dimensional study area; Combined with the seismic facies interpretation plates of different lithology combinations in the known three-dimensional study area, the seismic facies interpretation of the survey line in the two-dimensional area to be studied is carried out to determine the distribution characteristics of different lithology combinations and sandstone thickness on the survey line in the two-dimensional area to be studied; The 2D area sedimentary facies prediction is carried out based on multi-point geostatistics, with the seismic facies interpretation and drilling information of the 2D area to be studied as constraints; Under the constraints of the sedimentary facies prediction results of the two-dimensional area to be studied, the sandstone thickness in the two-dimensional area to be studied is predicted by using the two-point geostatistical method, combined with the sandstone thickness information of the drilled wells and the variogram information of the sandstone thickness in the known three-dimensional study area.

2. A multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method as claimed in claim 1, characterized in that: The establishment of a seismic facies interpretation chart of different lithology combinations at the well point locations in a known three-dimensional study area comprises the following steps: The seismic phase characteristics of different lithology combinations at the well point locations in the known three-dimensional study area are determined by well-seismic calibration; The seismic facies characteristics of different lithology combinations determined were verified through forward modeling; Based on the verified seismic facies characteristics of different lithology combinations, seismic facies interpretation maps of different lithology combinations are established.

3. The multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method according to claim 1, characterized in that: The two-dimensional area sedimentary facies prediction is carried out based on multi-point geostatistics, with the seismic facies interpretation of the survey line and drilling information of the two-dimensional area to be studied as constraints, including: The sedimentary facies study of the known three-dimensional study area is used as the training image; Build a pattern library based on training images; Based on the constructed model library, multi-point geostatistical phase simulation is carried out with the seismic phase interpretation of the survey line and drilling information of the two-dimensional area to be studied as constraints to realize the sedimentary phase prediction of the two-dimensional area to be studied.

4. A multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method as claimed in claim 3, characterized in that: The method of constructing a pattern library based on the training image includes: The size of the scanning window is determined according to the scale of different sedimentary facies types. The scanning window is used to identify the probability distribution of all possible attribute combinations from the training image to obtain a pattern library.

5. The multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method according to claim 3, characterized in that: For the predicted position u in the two-dimensional area to be studied, the sedimentary phase prediction result is expressed as P*, then: p * (u)=argmax p∈L d(u,p) Among them, d is a measure of the similarity between patterns.

6. The multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction method according to claim 1, characterized in that: The plane prediction result of the sandstone thickness in the two-dimensional area to be studied is expressed as: Where Z*(u) is the thickness of sandstone at the position u to be predicted, w n is the well data weight, Z n is the sandstone thickness at the well point, w k is the earthquake attribute weight, Y k is the seismic attribute related to the sandstone thickness of the drilling, N is the number of drilling wells, and K is the number of 2D seismic lines.

7. A phase-constrained sandstone thickness seismic prediction system based on multi-point geostatistics, characterized in that: include: "Point" phasing module is used to establish seismic facies interpretation charts of different lithology combinations at well point locations in a known 3D study area; The "Line" phase determination module is used to combine the seismic phase interpretation plates of different lithology combinations in the known three-dimensional study area to carry out seismic phase interpretation of the two-dimensional survey line to be studied, and determine the distribution characteristics of different lithology combinations and sandstone thickness on the two-dimensional survey line to be studied; The "surface" facies determination module is used to carry out sedimentary facies prediction in a two-dimensional area based on multi-point geostatistics, with the seismic facies interpretation of the two-dimensional survey line to be studied and the drilling information as constraints; The phase-constrained sandstone thickness simulation module is used to realize the sandstone prediction of the two-dimensional area to be studied by combining the drilled sandstone thickness information and the known three-dimensional sandstone thickness variation function under the constraint of the sedimentary phase prediction results of the two-dimensional area to be studied, using the two-point geostatistical method.

8. The multi-point geostatistics-based facies-constrained sandstone thickness seismic prediction system according to claim 6, characterized in that: The "face" phasing module comprises: A training data acquisition module is used to study the sedimentary facies of a known three-dimensional study area as a training image; A pattern library building module is used to build a pattern library based on training images; The 2D sedimentary facies prediction module is used to carry out multi-point geostatistical facies simulation based on the constructed model library, with the 2D survey line seismic facies interpretation and drilling information as constraints, and thus realize the sedimentary facies prediction of the 2D area to be studied.

9. A computer-readable storage medium storing one or more programs, characterized in that: The one or more programs include instructions, which, when executed by a computing device, cause the computing device to perform any one of the methods of claims 1 to 6.

10. A computing device, characterized in that include: One or more processors and a memory, wherein the memory stores one or more programs and is configured to be executed by the one or more processors, wherein the one or more programs include instructions for executing any one of the methods described in claims 1 to 6.

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