阅读说明：本技术 变偏移距vsp地表一致性振幅补偿方法和装置 (Variable offset VSP earth surface consistency amplitude compensation method and device ) 是由 李建国 于 2020-03-31 设计创作，主要内容包括：本发明提供了一种变偏移距VSP地表一致性振幅补偿方法和装置,该方法包括：根据零偏移距VSP,确定储层段弹性参数模型；根据变偏移距VPS记录,确定变偏移距VPS初至波极化角；根据储层段弹性参数模型和变偏移距VPS初至波极化角,确定储层段理论透射系数相对变化率；统计储层段实测透射能量,根据储层段实测透射能量,确定储层段实测透射能量相对变化率；根据储层段理论透射系数相对变化率和储层段实测透射能量相对变化率,确定地表一致性振幅补偿系数；根据地表一致性振幅补偿系数,多检波点统计共炮点地表一致性振幅补偿系数。有效解决了变偏移距VSP地表一致性振幅补偿的问题。(The invention provides a variable offset VSP earth surface consistency amplitude compensation method and a device, wherein the method comprises the following steps: determining a reservoir section elastic parameter model according to the zero offset VSP; determining a variable offset VPS first-arrival wave polarization angle according to the variable offset VPS record; determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle; counting the actually measured transmission energy of the reservoir section, and determining the relative change rate of the actually measured transmission energy of the reservoir section according to the actually measured transmission energy of the reservoir section; determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section; and according to the earth surface consistency amplitude compensation coefficient, counting the earth surface consistency amplitude compensation coefficient of the common shot point by multiple detection points. The problem of variable offset VSP earth surface consistency amplitude compensation is effectively solved.)

1. A variable offset VSP surface consistency amplitude compensation method is characterized by comprising the following steps:

determining a reservoir section elastic parameter model according to the zero offset VSP;

determining a variable offset VPS first-arrival wave polarization angle according to the variable offset VPS record;

determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

counting the actually measured transmission energy of the reservoir section, and determining the relative change rate of the actually measured transmission energy of the reservoir section according to the actually measured transmission energy of the reservoir section;

determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

and according to the earth surface consistency amplitude compensation coefficient, counting the earth surface consistency amplitude compensation coefficient of the common shot point by multiple detection points.

2. The method of claim 1, wherein the reservoir interval elastic parameter model comprises a reservoir interval compressional velocity model and a reservoir interval density model;

establishing a reservoir section longitudinal wave velocity model according to the following modes:

wherein H_iIs the ith detector depth, t_p,iIs the ith longitudinal wave first arrival, Offset is the distance from the VSP shot point to the well head at zero Offset, t_p,viIs the vertical single pass of the longitudinal wave of the ith detector;

V_p,i＝(H_i-H_i-1)/(t_p,vi-t_p,vi-1)

wherein H_i-1Is the depth of the i-1 th detector, H_iIs the ith detector depth, t_p,vi-1Is the vertical single pass of the longitudinal wave of the i-1 st detector, t_p,viWhen the longitudinal wave of the i-th detector is vertically single-pass, V_p,iIs the longitudinal wave velocity of the ith layer.

3. The method of claim 2, wherein the reservoir interval density model is created by resampling the sonic log density data to VSP depth samples.

4. The method of claim 1, wherein determining a variable offset VPS first arrival wave polarization angle from a variable offset VPS record comprises:

and recording the three-component variable offset VSP, and determining the polarization angle of the initial wave of the variable offset VPS according to the relation between the original ZXY coordinate system and the PRT coordinate system.

5. The method of claim 4, wherein the polarization angle of the offset-variant VPS first-arrival wave is determined as follows:

H＝X cosφ+Y sinφ

T＝X sinφ-Y cosφ

wherein, phi is a horizontal rotation angle, N is the number of sampling points in the first arrival time window, and HT is a horizontal radial component and a horizontal tangential component after XY horizontal rotation;

P＝Z cosθ+H sinθ

R＝Z sinθ-H cosθ

where θ is the polarization angle of the variable offset VPS first arrival wave, N is the number of sampling points in the first arrival time window, and PR is the vertical radial component and the vertical tangential component after ZH polarization rotation.

6. The method of claim 2, wherein determining the relative rate of change of the reservoir interval theoretical transmission coefficient based on the reservoir interval elastic parameter model and the variable offset VPS first arrival wave polarization angle comprises:

determining a theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

and determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the theoretical transmission coefficient of the reservoir section.

7. The method of claim 6, wherein the reservoir section theoretical transmission coefficient is determined as follows:

wherein, V_pIs a reservoir section longitudinal wave velocity model, V_p,1、V_p,2Is the longitudinal wave velocity above and below the interface, ρ is the reservoir section density model, ρ₁、ρ₂Is the density above and below the interface, T_ppAnd (theta) is a theoretical transmission coefficient with an incidence angle of theta, and the theta adopts a variable offset VPS first arrival wave polarization angle to replace the calculation of the theoretical transmission coefficient.

8. The method of claim 7, wherein the relative rate of change of the theoretical transmission coefficient of the reservoir section is determined as follows:

STPP_i＝T_pp(θ_i)/T_pp(0)

wherein, T_pp(θ_i) Is the angle of incidence theta_iTheoretical transmission coefficient of (1), T_pp(0) Is the theoretical transmission coefficient at an angle of incidence of 0, STPP_iIs the angle of incidence theta_iRelative rate of change of the theoretical transmission coefficient.

9. The method of claim 1, wherein the measured transmission energy of the reservoir section is counted as follows:

wherein N is the number of sampling points in the first arrival time window, Amp_iIs the amplitude, T, of the ith sample point in the first arrival time window_EngIs the transmitted wave energy of the first arrival time window.

10. The method of claim 9, wherein the relative rate of change of measured transmitted energy of the reservoir section is determined as follows:

MTPP_i＝T_Eng(θ_i)/T_Eng(0)

wherein, T_Eng(θ_i) Is the angle of incidence theta_iMeasured transmission energy of, T_Eng(0) Is the measured transmission energy at an angle of incidence of 0, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy.

11. The method of claim 1, wherein the surface-consistent amplitude compensation factor is determined as follows:

SCA_i＝MTPP_i/STPP_i

wherein, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy, STPP_iIs the angle of incidence theta_iRelative rate of change of theoretical transmission coefficient, SCA_iIs the angle of incidence theta_iThe earth surface uniformity amplitude compensation coefficient, the incidence angle theta_iCorresponding to the ith shot point, SCA_iI.e. the surface consistent amplitude compensation coefficient for the ith shot.

12. The method of claim 1, wherein the multiple-geophone point statistics co-shot surface consistency amplitude compensation coefficients are calculated as follows:

wherein N is the number of the wave detection points participating in the statistics, SCA_ijThe surface uniformity amplitude compensation coefficient, SCAS, of the jth demodulator probe of the ith shot point_iAnd (4) counting the earth surface consistency amplitude compensation coefficient of the common shot point by the N wave detection points of the ith shot point.

13. An amplitude compensation device for surface consistency of variable offset VSP, comprising:

the reservoir section elastic parameter model determining module is used for determining a reservoir section elastic parameter model according to the zero offset VSP;

the variable offset VPS first arrival wave polarization angle determining module is used for determining a variable offset VPS first arrival wave polarization angle according to the variable offset VPS record;

the reservoir section theoretical transmission coefficient relative change rate determining module is used for determining the reservoir section theoretical transmission coefficient relative change rate according to the reservoir section elastic parameter model and the variable offset VPS first arrival wave polarization angle;

the reservoir section actual measurement transmission energy relative change rate determining module is used for counting the reservoir section actual measurement transmission energy and determining the reservoir section actual measurement transmission energy relative change rate according to the reservoir section actual measurement transmission energy;

the earth surface consistency amplitude compensation coefficient determining module is used for determining an earth surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

and the multi-detection-point statistic common shot point earth surface consistency amplitude compensation coefficient module is used for counting common shot point earth surface consistency amplitude compensation coefficients according to the earth surface consistency amplitude compensation coefficients and the multi-detection-point statistic common shot point earth surface consistency amplitude compensation coefficients.

14. A computer apparatus comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor implementing the variable offset VSP surface uniformity amplitude compensation method of any one of claims 1-12 when executing the computer program.

15. A computer-readable storage medium storing a computer program for executing a method of implementing the variable offset VSP surface consistency amplitude compensation method according to any one of claims 1 to 12.

Technical Field

The invention relates to the technical field of seismic data processing in geophysical exploration, in particular to a method and a device for compensating earth surface consistency amplitude of a variable offset VSP (vertical seismic profiling).

Background

In recent years, the development of borehole seismic technology is rapid, and the variable offset VSP (namely, Walkaway VSP) is industrially applied. Changes in near-surface conditions, such as changes in regolith velocity, thickness, surface elevation, shot point, etc., result in large differences in seismic reflection amplitudes.

The amplitude difference of the surface non-uniformity must be removed before the stack, otherwise the subsequent deconvolution, velocity analysis, residual static correction, offset imaging and the like are influenced, and the accuracy of the pre-stack inversion and the post-stack inversion is further influenced.

The prior art has no technical scheme about variable offset VSP surface consistency amplitude compensation.

Disclosure of Invention

The embodiment of the invention provides a variable offset VSP earth surface consistency amplitude compensation method, which effectively solves the problem of variable offset VSP earth surface consistency amplitude compensation and comprises the following steps:

determining a reservoir section elastic parameter model according to the zero offset VSP;

determining a variable offset VPS first-arrival wave polarization angle according to the variable offset VPS record;

determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

counting the actually measured transmission energy of the reservoir section, and determining the relative change rate of the actually measured transmission energy of the reservoir section according to the actually measured transmission energy of the reservoir section;

determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

and according to the earth surface consistency amplitude compensation coefficient, counting the earth surface consistency amplitude compensation coefficient of the common shot point by multiple detection points.

The embodiment of the invention also provides a variable offset VSP earth surface consistency amplitude compensation device, which comprises:

the reservoir section elastic parameter model determining module is used for determining a reservoir section elastic parameter model according to the zero offset VSP;

the variable offset VPS first arrival wave polarization angle determining module is used for determining a variable offset VPS first arrival wave polarization angle according to the variable offset VPS record;

the reservoir section theoretical transmission coefficient relative change rate determining module is used for determining the reservoir section theoretical transmission coefficient relative change rate according to the reservoir section elastic parameter model and the variable offset VPS first arrival wave polarization angle;

the reservoir section actual measurement transmission energy relative change rate determining module is used for counting the reservoir section actual measurement transmission energy and determining the reservoir section actual measurement transmission energy relative change rate according to the reservoir section actual measurement transmission energy;

the earth surface consistency amplitude compensation coefficient determining module is used for determining an earth surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

and the multi-detection-point statistic common shot point earth surface consistency amplitude compensation coefficient module is used for counting common shot point earth surface consistency amplitude compensation coefficients according to the earth surface consistency amplitude compensation coefficients and the multi-detection-point statistic common shot point earth surface consistency amplitude compensation coefficients.

Embodiments of the present invention also provide a computer apparatus, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor implements the above method for compensating for amplitude of earth surface consistency of VSP with variable offset when executing the computer program.

Embodiments of the present invention also provide a computer-readable storage medium storing a computer program for implementing the variable offset VSP surface consistency amplitude compensation method.

According to the method and the device for compensating the earth surface consistency amplitude of the variable offset VSP, provided by the embodiment of the invention, the elastic parameter model of the reservoir section is established by using the zero offset VSP, the initial wave polarization angle of the variable offset VSP is taken as an incident angle, and the earth surface consistency amplitude compensation coefficient is calculated by using the difference between the relative change rate of the transmission energy and the relative change rate of a theoretical transmission coefficient, so that the problem of earth surface consistency amplitude compensation of the variable offset VSP is effectively solved. The method provides input data of relative amplitude preservation for the subsequent processing and imaging of the variable offset VSP, and preserves information of amplitude variation along with angle for prestack inversion.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts. In the drawings:

FIG. 1 is a schematic diagram of a method for compensating for the surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a reservoir segment compressional velocity model of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the invention.

FIG. 3 is a schematic diagram of a reservoir section density model of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the invention.

FIG. 4 is a schematic diagram of polarization angles of first-arrival waves of variable offset VPS according to an embodiment of the present invention.

FIG. 5 is a schematic diagram of theoretical transmission coefficients of a reservoir segment for a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the invention.

FIG. 6 is a schematic diagram of the measured transmission energy of a reservoir section of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the invention.

Fig. 7 is a schematic diagram of a common shot point surface consistency amplitude compensation coefficient of statistics of multiple wave detection points of a reservoir section according to a variable offset VSP surface consistency amplitude compensation method in an embodiment of the present invention.

FIG. 8 is a schematic diagram of the transmission energy of the variable offset VSP after reservoir segment surface consistency correction for the amplitude compensation method for the variable offset VSP surface consistency according to the embodiment of the invention.

Fig. 9 is a schematic diagram of a co-detector gather before earth surface consistency amplitude compensation in a variable offset VSP earth surface consistency amplitude compensation method according to an embodiment of the present invention.

Fig. 10 is a schematic diagram of a co-detector gather after earth surface consistency amplitude compensation according to an earth surface consistency amplitude compensation method for variable offset VSP earth surface consistency according to an embodiment of the present invention.

FIG. 11 is a schematic diagram of a computer device running a variable offset VSP surface uniformity amplitude compensation method implemented by the present invention.

FIG. 12 is a schematic diagram of an amplitude compensation apparatus for VSP surface uniformity with variable offset according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the embodiments of the present invention are further described in detail below with reference to the accompanying drawings. The exemplary embodiments and descriptions of the present invention are provided to explain the present invention, but not to limit the present invention.

As shown in fig. 1, a schematic diagram of a method for compensating the earth surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention, an embodiment of the present invention provides a method for compensating the earth surface consistency amplitude of the variable offset VSP, which effectively solves the problem of compensating the earth surface consistency amplitude of the variable offset VSP, and the method includes:

step 101: determining a reservoir section elastic parameter model according to the zero offset VSP;

step 102: determining a variable offset VPS first-arrival wave polarization angle according to the variable offset VPS record;

step 103: determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

step 104: counting the actually measured transmission energy of the reservoir section, and determining the relative change rate of the actually measured transmission energy of the reservoir section according to the actually measured transmission energy of the reservoir section;

step 105: determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

step 106: and according to the earth surface consistency amplitude compensation coefficient, counting the earth surface consistency amplitude compensation coefficient of the common shot point by multiple detection points.

According to the method for compensating the earth surface consistency amplitude of the variable offset VSP, provided by the embodiment of the invention, the elastic parameter model of the reservoir section is established by utilizing the zero offset VSP, the initial wave polarization angle of the variable offset VSP is taken as an incident angle, and the earth surface consistency amplitude compensation coefficient is calculated by utilizing the difference between the relative change rate of transmission energy and the relative change rate of a theoretical transmission coefficient, so that the problem of earth surface consistency amplitude compensation of the variable offset VSP is effectively solved. The method provides input data of relative amplitude preservation for the subsequent processing and imaging of the variable offset VSP, and preserves information of amplitude variation along with angle for prestack inversion.

The embodiment of the invention provides a variable offset VSP earth surface consistency amplitude compensation method, which comprises the following steps:

determining a reservoir section elastic parameter model according to the zero offset VSP; determining a variable offset VPS first-arrival wave polarization angle according to the variable offset VPS record; determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle; counting the actually measured transmission energy of the reservoir section, and determining the relative change rate of the actually measured transmission energy of the reservoir section according to the actually measured transmission energy of the reservoir section; determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section; and according to the earth surface consistency amplitude compensation coefficient, counting the earth surface consistency amplitude compensation coefficient of the common shot point by multiple detection points.

FIG. 2 is a schematic diagram of a reservoir interval compressional velocity model of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the present invention, in which the abscissa is compressional velocity (unit: m/s); the ordinate is the depth (unit: m). As shown in fig. 2, in the implementation of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the present invention, in an embodiment, the reservoir interval elastic parameter model includes a reservoir interval longitudinal wave velocity model and a reservoir interval density model;

establishing a reservoir section longitudinal wave velocity model according to the following modes:

wherein H_iIs the ith detector depth, t_p,iIs the ith longitudinal wave first arrival, Offset is the distance from the VSP shot point to the well head at zero Offset, t_p,viIs the vertical single pass of the longitudinal wave of the ith detector;

V_p,i＝(H_i-H_i-1)/(t_p,vi-t_p,vi-1)

wherein H_i-1Is the depth of the i-1 th detector, H_iIs the ith detector depth, t_p,vi-1Is the vertical single pass of the longitudinal wave of the i-1 st detector, t_p,viWhen the longitudinal wave of the i-th detector is vertically single-pass, V_p,iIs the longitudinal wave velocity of the ith layer.

The aforementioned expressions for establishing the longitudinal wave velocity model of the reservoir section are only examples, and those skilled in the art will understand that the above formula may be modified in some forms and other parameters or data may be added as needed, or other specific formulas may be provided, and these modifications are all within the scope of the present invention.

FIG. 3 is a schematic diagram of a reservoir section density model of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the invention, and the abscissa is density (unit: g/cm)³) (ii) a The ordinate is the depth (unit: m). In practicing a method for variable offset VSP surface consistency amplitude compensation according to embodiments of the present invention, as shown in fig. 3, in one embodiment, a reservoir interval density model is built by resampling VSP depth samples from the density data of sonic logs.

FIG. 4 is a schematic diagram of the polarization angle of the first arrival wave of the variable offset VPS in the amplitude compensation method for the earth surface consistency of the variable offset VSP according to the embodiment of the present invention, wherein the abscissa is the offset (unit: m); the ordinate represents the polarization angle (unit: °). As shown in fig. 4, in implementing a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the present invention, in an embodiment, determining a variable offset VPS first arrival wave polarization angle according to a variable offset VPS record includes:

and recording the three-component variable offset VSP, and determining the polarization angle of the initial wave of the variable offset VPS according to the relation between the original ZXY coordinate system and the PRT coordinate system.

In particular, in implementing a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the present invention, in one embodiment, the variable offset VPS first arrival wave polarization angle is determined as follows:

H＝X cosφ+Y sinφ

T＝X sinφ-Y cosφ

wherein, phi is a horizontal rotation angle, N is the number of sampling points in the first arrival time window, and HT is a horizontal radial component and a horizontal tangential component after XY horizontal rotation;

P＝Z cosθ+H sinθ

R＝Z sinθ-H cosθ

where θ is the polarization angle of the variable offset VPS first arrival wave, N is the number of sampling points in the first arrival time window, and PR is the vertical radial component and the vertical tangential component after ZH polarization rotation.

The aforementioned expression for determining the polarization angle of the first-arrival wave of the variable offset VPS is an example, and those skilled in the art will understand that the above formula may be modified in some forms and other parameters or data may be added as needed, or other specific formulas may be provided, and these modifications are all within the scope of the present invention.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation method according to the embodiments of the present invention, in one embodiment, determining a relative change rate of a theoretical transmission coefficient of a reservoir interval according to a reservoir interval elastic parameter model and a variable offset VPS first arrival wave polarization angle includes:

determining a theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

and determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the theoretical transmission coefficient of the reservoir section.

FIG. 5 is a schematic diagram of theoretical transmission coefficients of a reservoir interval of a method for compensating for surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention, with the abscissa being the angle of incidence (unit:); the ordinate is the transmission coefficient (unit: none). As shown in FIG. 5, in practicing a method of varying offset VSP surface consistency amplitude compensation in accordance with an embodiment of the present invention, in one embodiment, reservoir interval theoretical transmission coefficients are determined as follows:

wherein, V_pIs a reservoir section longitudinal wave velocity model, V_p,1、V_p,2Is the longitudinal wave velocity above and below the interface, ρ is the reservoir section density model, ρ₁、ρ₂Is the density above and below the interface, T_ppAnd (theta) is a theoretical transmission coefficient with an incidence angle of theta, and the theta adopts a variable offset VPS first arrival wave polarization angle to replace the calculation of the theoretical transmission coefficient.

The above mentioned expression for determining the theoretical transmission coefficient of the reservoir segment is an example, and it will be understood by those skilled in the art that the above formula may be modified in certain forms and other parameters or data may be added or other specific formulas may be provided according to the needs, and such modifications are within the scope of the present invention.

In particular, in implementing a method for compensating for the surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention, in one embodiment, the relative rate of change of the theoretical transmission coefficient of a reservoir interval is determined as follows:

STPP_i＝T_pp(θ_i)/T_pp(0)

wherein, T_pp(θ_i) Is the angle of incidence theta_iTheoretical transmission coefficient of (1), T_pp(0) Is the theoretical transmission coefficient at an angle of incidence of 0, STPP_iIs the angle of incidence theta_iRelative rate of change of the theoretical transmission coefficient.

The aforementioned expression for determining the relative change rate of the theoretical transmission coefficient of the reservoir segment is an example, and those skilled in the art will understand that the above formula may be modified in certain forms and other parameters or data may be added as required, or other specific formulas may be provided, and these modifications are all within the scope of the present invention.

FIG. 6 is a schematic diagram of the actually measured transmission energy of a reservoir section of a variable offset VSP surface consistency amplitude compensation method according to an embodiment of the present invention, where the abscissa is the offset (unit: m); the ordinate is amplitude energy (unit: none), and as shown in fig. 6, when the method for compensating the earth surface consistency of the variable offset VSP according to the embodiment of the present invention is implemented, in one embodiment, the measured transmission energy of the reservoir section is counted:

wherein N is the number of sampling points in the first arrival time window, Amp_iIs the amplitude, T, of the ith sample point in the first arrival time window_EngIs the transmitted wave energy of the first arrival time window.

The above mentioned expression for the measured transmission energy of the statistical reservoir segment is an example, and those skilled in the art will understand that the above formula may be modified in some forms and other parameters or data may be added as required, or other specific formulas may be provided, and these modifications are all within the scope of the present invention.

In particular, in implementing a variable offset VSP surface consistency amplitude compensation method of an embodiment of the present invention, in one embodiment, the relative rate of change of the measured transmission energy of a reservoir section is determined by:

MTPP_i＝T_Eng(θ_i)/T_Eng(0)

wherein, T_Eng(θ_i) Is the angle of incidence theta_iMeasured transmission energy of, T_Eng(0) Is the measured transmission energy at an angle of incidence of 0, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy.

The aforementioned expression for determining the relative rate of change of the measured transmission energy of the reservoir segment is an example, and those skilled in the art will understand that the above formula may be modified in certain forms and other parameters or data may be added as required, or other specific formulas may be provided, and such modifications are within the scope of the present invention.

In particular, in implementing a method for compensating for the earth surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention, in one embodiment, the earth surface consistency amplitude compensation coefficient is determined as follows:

SCA_i＝MTPP_i/STPP_i

wherein, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy, STPP_iIs the angle of incidence theta_iRelative rate of change of theoretical transmission coefficient, SCA_iIs the angle of incidence theta_iThe earth surface uniformity amplitude compensation coefficient, the incidence angle theta_iCorresponding to the ith shot point, SCA_iI.e. the surface consistent amplitude compensation coefficient for the ith shot.

The above mentioned expression for determining the earth surface consistency amplitude compensation factor is for illustration, and those skilled in the art will understand that the above formula may be modified in certain forms and other parameters or data may be added or other specific formulas may be provided according to the needs, and such modifications are within the scope of the present invention.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation method according to the embodiment of the present invention, in an embodiment, the common shot point surface consistency amplitude compensation coefficient is counted by multiple detection points as follows:

wherein N is the number of the wave detection points participating in the statistics, SCA_ijThe surface uniformity amplitude compensation coefficient, SCAS, of the jth demodulator probe of the ith shot point_iAnd (4) counting the earth surface consistency amplitude compensation coefficient of the common shot point by the N wave detection points of the ith shot point.

The aforementioned expression of the multiple-geophone-point statistical common-shot-point earth surface consistency amplitude compensation coefficient is an example, and those skilled in the art can understand that, in implementation, the above formula may be modified in a certain form and other parameters or data may be added as needed, or other specific formulas may be provided, and these modifications are all within the scope of the present invention.

FIG. 7 is a schematic diagram of a common shot point earth surface consistency amplitude compensation coefficient of statistics of multiple wave detection points of a reservoir section according to a variable offset VSP earth surface consistency amplitude compensation method of the present invention; the abscissa is the offset (unit: m); the ordinate is the amplitude compensation factor (unit: none). FIG. 8 is a schematic diagram of the transmission energy of the variable offset VSP after the reservoir section surface consistency correction of the amplitude compensation method for the variable offset VSP surface consistency according to the embodiment of the invention; the abscissa is the offset (unit: m); the ordinate is the amplitude energy (unit: none). FIG. 9 is a schematic diagram of a common detector gather before compensation of surface consistency amplitude according to a method for compensating surface consistency amplitude of a variable offset VSP according to an embodiment of the present invention; the abscissa is the offset (unit: m); the ordinate is time (unit: ms). FIG. 10 is a schematic diagram of a co-detector gather after compensation of surface-consistent amplitude for a variable offset VSP surface-consistent amplitude compensation method according to an embodiment of the present invention; the abscissa is the offset (unit: m); the ordinate is time (unit: ms).

As shown in fig. 11, an embodiment of the present invention further provides a computer apparatus, which includes a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor implements the variable offset VSP surface consistency amplitude compensation method when executing the computer program.

Embodiments of the present invention also provide a computer-readable storage medium storing a computer program for implementing the variable offset VSP surface consistency amplitude compensation method.

The embodiment of the invention also provides an amplitude compensation device for the surface consistency of the variable offset VSP, which is described in the following embodiment. Because the principle of solving the problem of the device is similar to a variable offset VSP surface consistency amplitude compensation method, the implementation of the device can refer to the implementation of the variable offset VSP surface consistency amplitude compensation method, and repeated details are not repeated.

As shown in fig. 12, an embodiment of the present invention further provides an amplitude compensation apparatus for varying offset VSP surface uniformity, including:

the reservoir section elastic parameter model determining module 1201 is used for determining a reservoir section elastic parameter model according to the zero offset VSP;

a variable offset VPS first arrival wave polarization angle determination module 1202, configured to determine a variable offset VPS first arrival wave polarization angle according to a variable offset VPS record;

a reservoir section theoretical transmission coefficient relative change rate determining module 1203, configured to determine a reservoir section theoretical transmission coefficient relative change rate according to the reservoir section elastic parameter model and the variable offset VPS first arrival wave polarization angle;

the reservoir section actual measurement transmission energy relative change rate determining module 1204 is used for counting the reservoir section actual measurement transmission energy and determining the reservoir section actual measurement transmission energy relative change rate according to the reservoir section actual measurement transmission energy;

a ground surface consistency amplitude compensation coefficient determining module 1205 for determining a ground surface consistency amplitude compensation coefficient according to the relative change rate of the theoretical transmission coefficient of the reservoir section and the relative change rate of the actually measured transmission energy of the reservoir section;

and the multiple-demodulator-point statistics common shot point earth surface consistency amplitude compensation coefficient module 1206 is used for counting the common shot point earth surface consistency amplitude compensation coefficient according to the earth surface consistency amplitude compensation coefficient and the multiple demodulator-points.

In the specific implementation of the variable offset VSP surface consistency amplitude compensation device according to the embodiment of the present invention, in one embodiment, the reservoir section elastic parameter model includes a reservoir section longitudinal wave velocity model and a reservoir section density model;

the reservoir section elastic parameter model determining module is further used for establishing a reservoir section longitudinal wave velocity model according to the following modes:

wherein H_iIs the ith detector depth, t_p,iIs the ith longitudinal wave first arrival, Offset is the distance from the VSP shot point to the well head at zero Offset, t_p,viIs the vertical single pass of the longitudinal wave of the ith detector;

V_p,i＝(H_i-H_i-1)/(t_p,vi-t_p,vi-1)

wherein H_i-1Is the depth of the i-1 th detector, H_iIs the ith detector depth, t_p,vi-1Is the vertical single pass of the longitudinal wave of the i-1 st detector, t_p,viWhen the longitudinal wave of the i-th detector is vertically single-pass, V_p,iIs the longitudinal wave velocity of the ith layer.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the present invention, in an embodiment, the reservoir section elastic parameter model determining module is further configured to resample the density data of the sonic logging into VSP depth samples, and establish the reservoir section density model.

In an embodiment of the invention, when the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the invention is implemented, the variable offset VPS first-arrival wave polarization angle determination module is specifically configured to:

and recording the three-component variable offset VSP, and determining the polarization angle of the initial wave of the variable offset VPS according to the relation between the original ZXY coordinate system and the PRT coordinate system.

In an embodiment of the invention, when the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the invention is implemented, the variable offset VPS first-arrival polarization angle determination module is further configured to determine the variable offset VPS first-arrival polarization angle as follows:

H＝X cosφ+Y sinφ

T＝X sinφ-Y cosφ

wherein, phi is a horizontal rotation angle, N is the number of sampling points in the first arrival time window, and HT is a horizontal radial component and a horizontal tangential component after XY horizontal rotation;

P＝Z cosθ+H sinθ

R＝Z sinθ-H cosθ

where θ is the polarization angle of the variable offset VPS first arrival wave, N is the number of sampling points in the first arrival time window, and PR is the vertical radial component and the vertical tangential component after ZH polarization rotation.

In an embodiment of the invention, when the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the invention is embodied, the reservoir section theoretical transmission coefficient relative change rate determination module is specifically configured to:

determining a theoretical transmission coefficient of the reservoir section according to the elastic parameter model of the reservoir section and the variable offset VPS first arrival wave polarization angle;

and determining the relative change rate of the theoretical transmission coefficient of the reservoir section according to the theoretical transmission coefficient of the reservoir section.

In particular, in implementing the variable offset VSP surface consistency amplitude compensation apparatus according to an embodiment of the present invention, in an embodiment, the reservoir segment theoretical transmission coefficient relative change rate determining module is further configured to determine the reservoir segment theoretical transmission coefficient as follows:

wherein, V_pIs a reservoir section longitudinal wave velocity model, V_p,1、V_p,2Is the longitudinal wave velocity above and below the interface, ρ is the reservoir section density model, ρ₁、ρ₂Is the density above and below the interface, T_ppAnd (theta) is a theoretical transmission coefficient with an incidence angle of theta, and the theta adopts a variable offset VPS first arrival wave polarization angle to replace the calculation of the theoretical transmission coefficient.

In particular, in implementing the variable offset VSP surface consistency amplitude compensation apparatus according to an embodiment of the present invention, in an embodiment, the reservoir segment theoretical transmission coefficient relative change rate determining module is further configured to determine the reservoir segment theoretical transmission coefficient relative change rate according to the following manner:

STPP_i＝T_pp(θ_i)/T_pp(0)

wherein, T_pp(θ_i) Is the angle of incidence theta_iTheoretical transmission coefficient of (1), T_pp(0) Is the theoretical transmission coefficient at an angle of incidence of 0, STPP_iIs the angle of incidence theta_iRelative rate of change of the theoretical transmission coefficient.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the present invention, in an embodiment, the module for determining a relative change rate of actually measured transmission energy of the reservoir segment is specifically configured to count the actually measured transmission energy of the reservoir segment as follows:

wherein N is the number of sampling points in the first arrival time window, Amp_iIs the amplitude, T, of the ith sample point in the first arrival time window_EngIs the transmitted wave energy of the first arrival time window.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation apparatus according to an embodiment of the present invention, in an embodiment, the module for determining a relative change rate of measured transmission energy of the reservoir segment is further configured to determine the relative change rate of measured transmission energy of the reservoir segment as follows:

MTPP_i＝T_Eng(θ_i)/T_Eng(0)

wherein, T_Eng(θ_i) Is the angle of incidence theta_iMeasured transmission energy of, T_Eng(0) Is the measured transmission energy at an angle of incidence of 0, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy.

In particular, when implementing the variable offset VSP surface consistency amplitude compensation apparatus according to an embodiment of the present invention, in an embodiment, the surface consistency amplitude compensation coefficient determining module is specifically configured to determine the surface consistency amplitude compensation coefficient as follows:

SCA_i＝MTPP_i/STPP_i

wherein, MTPP_iIs the angle of incidence theta_iRelative rate of change of measured transmitted energy, STPP_iIs the angle of incidence theta_iRelative rate of change of theoretical transmission coefficient, SCA_iIs the angle of incidence theta_iThe earth surface uniformity amplitude compensation coefficient, the incidence angle theta_iCorresponding to the ith shot point, SCA_iI.e. the surface consistent amplitude compensation coefficient for the ith shot.

In a specific implementation of the variable offset VSP surface consistency amplitude compensation apparatus according to the embodiment of the present invention, in an embodiment, the multi-probe statistics common shot point surface consistency amplitude compensation coefficient module is specifically configured to perform multi-probe statistics common shot point surface consistency amplitude compensation coefficients as follows:

wherein N is the number of the wave detection points participating in the statistics, SCA_ijThe surface uniformity amplitude compensation coefficient, SCAS, of the jth demodulator probe of the ith shot point_iAnd (4) counting the earth surface consistency amplitude compensation coefficient of the common shot point by the N wave detection points of the ith shot point.

In summary, according to the method and device for compensating earth surface consistency amplitude of the variable offset VSP provided by the embodiment of the present invention, a reservoir section elastic parameter model is established by using a zero offset VSP, a theoretical transmission coefficient at a simulated detector is forward-simulated by using a first arrival wave polarization angle of the variable offset VSP as an incident angle, and a theoretical change rate of transmission coefficients at various angles is calculated by using a zero degree transmission coefficient as a reference. The method is characterized in that the energy of first-arrival transmission waves of each shot point is counted, the energy change rate of the first-arrival transmission waves is calculated by taking a wellhead channel as a reference, the difference between the energy change rate and a theoretical change rate is counted by multiple wave detection points, the earth surface consistency amplitude compensation coefficient of each shot point is calculated, and the problem of earth surface consistency amplitude compensation of the variable offset VSP is effectively solved. The method provides input data of relative amplitude preservation for the subsequent processing and imaging of the variable offset VSP, and preserves information of amplitude variation along with angle for prestack inversion.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention 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 the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. 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-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.