Method and device for establishing seismic horizon velocity model of target stratum, medium and equipment

Abstract

The invention discloses a target stratum seismic horizon velocity model establishment method and device, a medium and equipment. The target stratum seismic horizon velocity model establishment method comprises the following steps: acquiring data of seismic horizon velocity of an adjacent well; selecting two adjacent wells, and communicating a target layer on a seismic section; based on the seismic section, establishing a well-connecting geological section; determining two influence factors influencing the interval velocity; and establishing an interval velocity model. According to the objective stratum seismic interval velocity model establishment method, the interval velocity model is established, and the interval velocity value of a drilled well is substituted into the model to calculate the interval velocity of a deployed well, so that the calculation accuracy of the objective stratum seismic interval velocity of a risk exploratory well can be improved, and a foundation is laid for predicting the depth of the objective stratum and formulating a drilling progress plan. And technical support is provided for evaluating economic benefits.

Description

Technical Field

[0001] This invention relates to the fields of petroleum and natural gas geology and exploration and development technology, and in particular to a method, apparatus, medium and equipment for establishing a seismic velocity model of a target layer. Background Technology

[0002] Seismic layer velocity refers to the speed at which seismic waves propagate in layered strata. It directly reflects the lithology of the strata and can be used to delineate them. In homogeneous strata, the speed at which seismic waves propagate is also relevant. Accurate calculation of seismic layer velocity is particularly important for predicting the depth of risky exploration wells, directly affecting the target layer depth, drilling schedule, and economic benefit evaluation. Therefore, establishing a model for the seismic layer velocity of the target layer is crucial.

[0003] In the prior art, the method for establishing an initial depth layer velocity model by combining seismic geological knowledge, as disclosed in "CN104360385B", fully absorbs the advantages of the three existing methods for establishing initial depth layer velocity models. At the same time, it adopts the idea of ​​multi-information constraints to comprehensively establish the initial depth layer velocity model, making the initial depth layer velocity model more accurate.

[0004] However, the model established by this method still cannot accurately calculate the seismic velocity of the target seismic layer in risk exploration wells, which leads to the inability to accurately calculate the depth of the deployed exploration wells, thus causing errors in predicting the depth of the target layer, formulating drilling schedules, and evaluating economic benefits. Summary of the Invention

[0005] The main objective of this invention is to provide a method, apparatus, medium, and equipment for establishing a seismic velocity model of a target layer, aiming to solve the technical problem in the prior art that it is impossible to accurately calculate the depth of deployed exploration wells.

[0006] To achieve the above objectives, the present invention provides a method for establishing a seismic layer velocity model for a target layer. The method includes: acquiring seismic layer velocity data from adjacent wells; selecting two adjacent wells and connecting them to the target layer on a seismic profile; establishing a connected well geological profile based on the seismic profile; determining the two major influencing factors affecting layer velocity; and establishing a layer velocity model.

[0007] Optionally, the seismic velocity data of the adjacent well is obtained by VSP logging calculation.

[0008] Optionally, the determination of the two major influencing factors affecting the layer velocity includes: marking the depth of the target layer that has been drilled, the distance between wells, and the layer velocity value; establishing a model based on the layer velocity, distance, and burial depth of adjacent wells; and determining the two major influencing factors affecting the layer velocity based on geostatistical analysis.

[0009] Optionally, the two main factors affecting the velocity of the influencing layer include distance and burial depth.

[0010] Optionally, after determining the two major influencing factors affecting the layer velocity based on the geostatistical analysis, the method further includes: marking the distance between the three wells and the burial depth of the target layer on the seismic profile.

[0011] Optionally, establishing the layer velocity model includes: abstracting and establishing a mathematical model based on the calibration of seismic profiles, wherein the mathematical model is a quadratic equation with a parabolic shape; and establishing the layer velocity model based on surrounding drilled wells and the following formula:

[0012] y=f1(t1,t2)x2+f2(k1,k2,k3)x+f3(t1,t2,k1,k2,k3) (1)

[0013] In this context, the two adjacent wells are represented by well A and well B, the deployed well is represented by well C, t1 represents the distance between well A and well B; t2 represents the distance between well B and well C; k1 represents the depth of well A; k2 represents the depth of well B; k3 represents the depth of well C; y represents the velocity of the unknown layer; and x represents the velocity of the drilled layer.

[0014] Optionally, after establishing the layer velocity model, the method further includes: substituting the layer velocity values ​​of the drilled wells into the model to calculate the layer velocity of the deployed wells.

[0015] Furthermore, to achieve the above objectives, this application embodiment also provides a device for calculating the seismic layer velocity of a target layer. The device includes: an acquisition module for acquiring seismic layer velocity data from adjacent wells; a selection module for selecting two adjacent wells and connecting them to the target layer on a seismic profile; a profile establishment module for establishing a connected well geological profile based on the seismic profile; a determination module for determining the two major influencing factors affecting the layer velocity; and a model establishment module for establishing a layer velocity model.

[0016] In addition, to achieve the above objectives, embodiments of this application also provide a computer-readable storage medium including instructions that, when executed on a computer, cause the computer to perform the method for establishing a target layer seismic velocity model as described in any embodiment of this application.

[0017] Furthermore, to achieve the above objectives, embodiments of this application also provide a computing device, which includes at least one processor, a memory, and an input / output unit; wherein the memory is used to store a computer program, and the processor is used to call the computer program stored in the memory to execute the target layer seismic layer velocity model establishment method described in any embodiment of this application.

[0018] This application provides a method, apparatus, medium, and equipment for establishing a seismic velocity model for a target layer. By establishing a layer velocity model, the layer velocity values ​​of drilled wells are substituted into the model to calculate the layer velocity of deployed wells. This model can improve the accuracy of seismic velocity calculation for target layers in risk exploration wells, providing technical support for predicting the depth of the target layer, formulating drilling schedules, and evaluating economic benefits. Attached Figure Description

[0019] Figure 1 A flowchart illustrating the method for establishing a target layer seismic velocity model provided in this application embodiment;

[0020] Figure 2 A structural block diagram of the device for calculating the seismic velocity of the target layer provided in the embodiments of this application;

[0021] Figure 3 A schematic diagram of the structure of a medium provided in an embodiment of this application;

[0022] Figure 4 This is a schematic diagram of the structure of a computing device provided in an embodiment of this application;

[0023] Figure 5 This is a mathematical model of the seismic velocity of the target layer provided in the embodiments of this application.

[0024] Explanation of reference numerals in the attached figures:

[0025] 300 - Calculation device for seismic layer velocity of target layer, 310 - Acquisition module, 320 - Selection module, 330 - Profile creation module, 340 - Determination module, 350 - Model creation module, 360 - Calculation module.

[0026] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the application. Rather, these embodiments are provided to make the disclosure more thorough and complete, and to fully convey the scope of the disclosure to those skilled in the art.

[0028] To address the aforementioned technical problems, embodiments of this application provide a method for establishing a seismic layer velocity model for a target layer, such as... Figure 1 As shown, the method may include the following steps:

[0029] S10, acquire data on the seismic velocity of adjacent well layers.

[0030] The seismic velocity data of the adjacent well can be obtained through VSP logging.

[0031] Specifically, VSP logging is a high-resolution seismic exploration technique and a well logging method that combines the characteristics of both seismic and well logging, serving as a "bridge" between seismic, well logging, and geological information. VSP logging, short for Vertical Seismic Profiling, is a seismic technique developed based on well logging. This technique obtains formation reflection information by generating seismic waves in the well and observing them at geophones placed at different depths on the surface or within the well. Because the geophones are placed inside the formation through the well, VSP logging can receive not only upward-propagating P-waves and upward-converted waves, but also downward-propagating P-waves and downward-converted waves, and even S-waves. This gives VSP logging unique advantages in studying subsurface lithology, performing seismic wave group stratigraphic calibration, and providing support for seismic data processing and interpretation.

[0032] Furthermore, VSP logging technology is characterized by a high signal-to-noise ratio, high resolution, and the ability to clearly observe the kinematic and dynamic features of waves. These characteristics make VSP logging an important technology for resource discovery in new oil and gas exploration areas and for in-depth analysis of old oilfields. Compared with conventional surface seismic exploration, VSP logging has higher accuracy in extracting formation geological parameters, formation velocities, seismic wavelets, and other seismic parameters. Currently, most oil and gas fields in China have entered the middle and late stages of development, and the market for discovering oil and gas fields mainly through surface exploration is shrinking. VSP logging, on the other hand, demonstrates unique advantages in fine reservoir characterization and the development of remaining oil.

[0033] S20, select two adjacent wells and connect the target layer on the seismic profile.

[0034] Specifically, a geological profile is a map at a certain scale that represents geological phenomena and their interrelationships on a geological section; it is a depth-domain profile. A seismic profile, on the other hand, is a profile of subsurface impedance reflection interfaces formed through data acquisition and processing. Combined with drilling and logging data to create a synthetic record, it integrates the seismic profile with geological stratification; this can be in the time domain or the depth domain. While a seismic profile is a profile of subsurface impedance reflection interfaces formed through data acquisition and processing, geological profiles and seismic profiles are not necessarily related; they are not mutually dependent but both reflect subsurface geological morphology.

[0035] S30, based on seismic profiles, establishes a geological profile connecting wells.

[0036] S40 identifies the two main factors affecting the velocity of the layer.

[0037] In an exemplary embodiment, step S40 may include the following steps:

[0038] S410 indicates the depth of the drilled target layer, the distance between wells, and the layer velocity value;

[0039] S420, a model is built based on the layer velocity, distance, and burial depth of adjacent wells;

[0040] Based on geostatistical analysis, S430 identifies two major influencing factors affecting the velocity of the layer.

[0041] Specifically, the two main factors affecting the velocity of the influencing layer are distance and burial depth.

[0042] In an exemplary embodiment, after step S430, the method further includes:

[0043] Mark the distance between the three wells and the burial depth of the target layer on the seismic profile.

[0044] The depth of the target layer refers to the distance from the target layer to the bottom of the foundation, and is simply called the depth.

[0045] S50, establish the layer velocity model.

[0046] In an exemplary embodiment, step S50 may include the following steps:

[0047] S510, based on the calibration of seismic profiles, an abstract mathematical model is established, which is a quadratic equation in one variable with a parabolic shape;

[0048] S520, based on surrounding drilled wells and the following formula, establishes a layer velocity model:

[0049] y = f1(t1,t2)x 2 +f2(k1,k2,k3)x+f3(t1,t2,k1,k2,k3) (1)

[0050] In this context, the two adjacent wells are represented by well A and well B, the deployed well is represented by well C, t1 represents the distance between well A and well B; t2 represents the distance between well B and well C; k1 represents the depth of well A; k2 represents the depth of well B; k3 represents the depth of well C; y represents the velocity of the unknown layer; and x represents the velocity of the drilled layer.

[0051] In an exemplary embodiment, after step S50, the method further includes:

[0052] S60, substitute the layer velocity values ​​of the drilled wells into the model to calculate the layer velocity of the deployed well.

[0053] The embodiments of this application will now be described in more detail:

[0054] S1. Obtain seismic layer velocity data from adjacent wells. The data was obtained through VSP logging and drilling calibration calculations. The layer velocity of the Triassic Baikouquan Formation in well Shimo 1 is 4500 m / s, and the layer velocity of the Triassic Baikouquan Formation in well Moshen 1 is 4800 m / s.

[0055] S2, select two adjacent wells and connect the target layer on the seismic profile; connect the Triassic Baikouquan Formation of Moshen 1 Well, Modong 1 Well, and Shimo 1 Well on the seismic profile.

[0056] S3, Determining the main controlling factors of formation velocity: Formation velocity is mainly controlled by formation lithology, depth, pore structure, and pore fluid. It is characterized by the fact that the deeper the formation, the greater the velocity of the same formation. Based on the seismic profile, a geological profile connecting wells is established, marking the depth of the target layer of the drilled wells, the distance between wells, and the formation velocity value. K3 is 4488m, K1 is 5939m, t1 is 25.7km, and t2 is 26.34km.

[0057] S4, Establish the layer velocity model: Through the calibration of seismic profiles, an abstract mathematical model is established, which is a quadratic equation with a parabolic shape.

[0058] S5, Reference Figure 5 A layer velocity model is established using surrounding drilled wells, as shown in the following formula.

[0059] y = -9E -5 x 2 + 1.1641x + 1124.8 (2)

[0060] S6. Substitute the layer velocity values ​​of the drilled wells into the model to calculate the layer velocity of the deployed well. The layer velocity of the Triassic Baikouquan Formation in the Moshen 1 well is calculated to be 4680 m / s.

[0061] This application provides a method for establishing a seismic velocity model for a target layer. By establishing a layer velocity model, the layer velocity values ​​of drilled wells are substituted into the model to calculate the layer velocity of the deployed wells. This improves the accuracy of seismic velocity calculation for the target layer in risk exploration wells, and provides technical support for predicting the depth of the target layer, formulating drilling schedules, and evaluating economic benefits.

[0062] Based on the above embodiments, refer to Figure 2 Another embodiment of this application also provides a target layer seismic velocity model establishment device 300, which may include the following modules:

[0063] Module 310 is used to acquire data on the seismic velocity of adjacent wells;

[0064] Select module 320 to select two adjacent wells and connect the target layer on the seismic profile;

[0065] Profile creation module 330 is used to create well-connected geological profiles based on seismic profiles;

[0066] Indeed, module 340 is used to determine the two major influencing factors affecting the speed of the layer;

[0067] Model building module 350 is used to build layer velocity models.

[0068] Based on the above embodiments, this application also provides a computer-readable storage medium, see reference. Figure 3 The computer-readable storage medium shown is an optical disc 50, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it implements the steps described in the above-described method implementation, such as: acquiring seismic layer velocity data of adjacent wells; selecting two adjacent wells and connecting the target layer on the seismic profile; establishing a connected well geological profile based on the seismic profile; determining the two major influencing factors affecting layer velocity; establishing a layer velocity model; and substituting the layer velocity values ​​of the drilled wells into the model to calculate the layer velocity of the deployed well. The specific implementation methods of each step will not be repeated here.

[0069] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical and magnetic storage media, which will not be elaborated here.

[0070] Furthermore, based on the above embodiments, this application also provides a computing device. Figure 4 A block diagram is shown of an exemplary computing device 60 suitable for implementing embodiments of the present application. The computing device 60 may be a computer system or a server. Figure 4 The computing device 60 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0071] like Figure 4 As shown, the components of computing device 60 may include, but are not limited to: one or more processors or processing units 601, system memory 602, and bus 603 connecting different system components (including system memory 602 and processing unit 601).

[0072] The computing device 60 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the computing device 60, including volatile and non-volatile media, removable and non-removable media.

[0073] System memory 602 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 6021 and / or cache memory 6022. Computing device 60 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, ROM 6023 may be used to read and write non-removable, non-volatile magnetic media (…). Figure 4 Not shown in the image (usually referred to as a "hard drive"). Although not shown in Figure 4 The diagram illustrates that disk drives for reading and writing to removable non-volatile disks (e.g., "floppy disks") and optical disc drives for reading and writing to removable non-volatile optical discs (e.g., CD-ROMs, DVD-ROMs, or other optical media) can be provided. In these cases, each drive can be connected to a bus 603 that connects different system components via one or more data media interfaces. The system memory 602 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments of this application.

[0074] A program / utility 6025 having a set (at least one) of program modules 6024 may be stored, for example, in system memory 602, and such program modules 6024 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment. Program modules 6024 typically perform the functions and / or methods described in the embodiments of this application.

[0075] The computing device 60 can also communicate with one or more external devices 604 (such as a keyboard, pointing device, display, etc.). This communication can be performed via the input / output (I / O) interface 605. Furthermore, the computing device 60 can also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter 606. Figure 4 As shown, network adapter 606 communicates with other modules of computing device 60 (such as processing unit 601, etc.) via bus 603, which connects different system components. It should be understood that, although... Figure 4 Other hardware and / or software modules may be used in conjunction with computing device 60, as not shown in the diagram.

[0076] The processing unit 601 executes various functional applications and data processing by running programs stored in the system memory 602. For example, it acquires seismic layer velocity data from adjacent wells; selects two adjacent wells and connects them to the target layer on the seismic profile; establishes a connected well geological profile based on the seismic profile; determines the two major influencing factors affecting layer velocity; establishes a layer velocity model; and calculates the layer velocity of the deployed well by substituting the layer velocity values ​​of the drilled wells into the model. The specific implementation methods of each step will not be repeated here. It should be noted that although several units / modules or sub-units / sub-modules of the device for calculating the seismic layer velocity of the target layer are mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided and embodied by multiple units / modules.

[0077] In the description of this application, it should be noted that the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0078] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0079] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0080] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0081] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0082] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0083] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

[0084] Furthermore, although the operations of the method of this application are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

Claims

1. A method for establishing a seismic layer velocity model for a target layer, characterized in that, The method for establishing the seismic velocity model of the target layer includes: Acquire seismic velocity data from adjacent wells; Select two adjacent wells and connect the target layer on the seismic profile; Establish a well-connected geological profile based on seismic profiles; Identify the two main factors influencing the velocity of the influencing layer; Establish a layer velocity model.

2. The method for establishing the seismic velocity model of the target layer according to claim 1, characterized in that, The seismic velocity data of the adjacent well was obtained through VSP logging calculations.

3. The method for establishing the seismic velocity model of the target layer according to claim 1, characterized in that, The two main influencing factors for determining the velocity of the affected layer include: Mark the depth of the drilled target layer, the distance between wells, and the layer velocity value; A model was established based on the layer velocity, distance, and burial depth of adjacent wells; Based on geostatistical analysis, two major influencing factors affecting the velocity of the layer were identified.

4. The method for establishing the seismic velocity model of the target layer according to claim 3, characterized in that, The two main factors influencing the velocity of the influencing layer are distance and burial depth.

5. The method for establishing the seismic velocity model of the target layer according to claim 3, characterized in that, After identifying the two major influencing factors of the velocity of the influencing layer based on geostatistical analysis, the method further includes: Mark the distance between the three wells and the burial depth of the target layer on the seismic profile.

6. The method for establishing the seismic velocity model of the target layer according to claim 1, characterized in that, The establishment of the layer velocity model includes: Based on the calibration of seismic profiles, an abstract mathematical model is established, which is a quadratic equation in one variable with a parabolic shape. A layer velocity model is established based on surrounding drilled wells and the following formula: y=f1(t1,t2)x 2 +f2(k1,k2,k3)x+f3(t1,t2,k1,k2,k3) (1) In this context, the two adjacent wells are represented by well A and well B, the deployed well is represented by well C, t1 represents the distance between well A and well B; t2 represents the distance between well B and well C; k1 represents the depth of well A; k2 represents the depth of well B; k3 represents the depth of well C; y represents the velocity of the unknown layer; and x represents the velocity of the drilled layer.

7. The method for establishing the seismic velocity model of the target layer according to claim 1, characterized in that, After establishing the layer velocity model, the method further includes: The layer velocity values ​​of the drilled wells are substituted into the model to calculate the layer velocity of the deployed wells.

8. A device for establishing a seismic layer velocity model for a target layer, characterized in that, include: The acquisition module is used to acquire data on the seismic velocity of adjacent wells; The selection module is used to select two adjacent wells and connect the target layer on the seismic profile. The profile creation module is used to create well-connected geological profiles based on seismic profiles. The determination module is used to identify the two main influencing factors affecting the velocity of the layer. The model building module is used to build layer velocity models.

9. A computer-readable storage medium, characterized in that, It includes instructions that, when run on a computer, cause the computer to perform the method for establishing the target layer seismic layer velocity model as described in any one of claims 1 to 7.

10. A computing device, characterized in that, The computing device includes: At least one processor, memory, and input / output unit; The memory is used to store computer programs, and the processor is used to call the computer programs stored in the memory to execute the method for establishing the seismic velocity model of the target layer as described in any one of claims 1 to 7.

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