CN103135134B - The defining method of scalar shear wave and device in 3-D seismics resilient bias detection wave field - Google Patents

Abstract

The invention provides defining method and the device of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, the method comprises: carry out curl computing to detection wave field, obtains vector shear wave; Calculate the direction of propagation of source wavefield and the direction of propagation of detection wave field; Calculate the vector product of the direction of propagation of source wavefield and the direction of propagation of detection wave field; According to the vector product of the direction of propagation of vector shear wave, source wavefield and the direction of propagation of detection wave field, determine the symbol of scalar shear wave; According to the absolute value of vector shear wave and the symbol of scalar shear wave, obtain scalar shear wave.The present invention can determine scalar shear wave in three-dimensional detection wave field, can be applicable to the reflection converted shear wave imaging in 3-D seismics resilient bias, the physical significance of reflection converted shear wave imaging results that the scalar shear wave obtained according to the inventive method obtains is more clear and definite, and the seismic interpretation being more conducive to the later stage is applied.

Description

The defining method of scalar shear wave and device in 3-D seismics resilient bias detection wave field

Technical field

The present invention relates to exploration geophysics field, particularly, relate to defining method and the device of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field.

Background technology

In current three dimensional seismic data elasticity reverse-time migration imaging, conventional Helmholtz wave field separation technology does divergence computing to elastic wave field (comprising source wavefield and detection wave field) to obtain compressional wave, do curl computing acquisition shear wave, the compressional wave that the method obtains is scalar form, the shear wave obtained is then vector form, but the shear wave (hereinafter referred to as vector shear wave) of this vector form is different in the application of two-dimensional case and three-dimensional situation.In the application of two-dimensional case, vector shear wave only has a nonzero component, is actually SV ripple, therefore can apply as scalar wave; And in the application of three-dimensional situation, vector shear wave is then a three-component vector.In the reverse-time migration of 3-D seismics elasticity, cross-correlation image-forming condition requires to carry out imaging using the ripple of scalar form as input, and the vector shear wave that therefore wave field separation method obtains at present cannot be used for the reverse-time migration of 3-D seismics elasticity.

Summary of the invention

The fundamental purpose of the embodiment of the present invention is the defining method and the device that provide scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, to solve the problem that existing Helmholtz wave field separation technology can not extract 3-D seismics scalar shear wave.

To achieve these goals, the embodiment of the present invention provides the defining method of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, and the method comprises:

Curl computing is carried out to detection wave field, obtains vector shear wave;

Calculate the direction of propagation of source wavefield and the direction of propagation of detection wave field;

Calculate the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field;

According to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determine the symbol of scalar shear wave;

According to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtain scalar shear wave.

Accordingly, the present invention also provides the determining device of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, and this device comprises:

Vector shear wave acquisition module, for carrying out curl computing to detection wave field, obtains vector shear wave;

Direction of propagation computing module, for the direction of propagation of the direction of propagation and detection wave field that calculate source wavefield;

Vector product computing module, for the vector product of the direction of propagation of the direction of propagation and detection wave field that calculate described source wavefield;

Symbol determination module, for the vector product according to the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determines the symbol of scalar shear wave;

Scalar shear wave determination module, for according to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtains scalar shear wave.

By means of technique scheme, the present invention can determine scalar shear wave in three-dimensional detection wave field, can be applicable to reflection converted shear wave (the i.e. PS ripple) imaging in 3-D seismics resilient bias, the imaging results that vector shear wave obtains vector reflection converted shear wave was directly applied compared to existing technology, the physical significance of reflection converted shear wave imaging results that the scalar shear wave obtained according to the inventive method obtains is more clear and definite, and the seismic interpretation being more conducive to the later stage is applied.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, below the accompanying drawing used required in describing embodiment is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.

Fig. 1 is the schematic flow sheet of the defining method of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention;

Fig. 2 is the velocity of longitudinal wave of the three-dimensional tilt interfacial medium model that the embodiment of the present invention one provides;

Fig. 3 is the detection wave field in a certain moment in the hour offset of model inversion shown in Fig. 2 process;

Fig. 4 is the vector shear wave field that wave field shown in Fig. 3 obtains through curl computing;

Fig. 5 is the detection wave field scalar shear wave that the embodiment of the present invention one provides;

Fig. 6 is optimized the filtered scalar shear wave obtained to the scalar shear wave shown in Fig. 5;

Fig. 7 carries out elasticity inverse time inclined obtained final stacking image result to the interfacial medium of three-dimensional tilt shown in Fig. 2 model;

Fig. 8 is the 3 D complex dielectric model that the embodiment of the present invention two provides;

Fig. 9 (a) is the PS converted wave imaging result that the embodiment of the present invention two provides;

Fig. 9 (b) is the PP ripple imaging results that the embodiment of the present invention two provides;

Figure 10 is the determination apparatus structure block diagram of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

The vector shear wave obtained by asking curl computing to elastic wave field is shear wave particle vibration curl of vector in essence, therefore this vector shear wave simultaneously with horizontal direction of wave travel and particle vibration direction perpendicular.In Three-Dimensional Isotropic medium, the incident wave direction of propagation at reflection spot place, the reflected P-wave direction of propagation and the reflection wave direction of propagation are all positioned at same plane, be called ray plane, when incident wave is compressional wave, the particle vibration of reflection wave is also positioned at ray plane.Therefore, when compressional wave incidence, by the direction vector of the vector shear wave of asking curl to obtain to elastic wave field and ray plane perpendicular.

Based on above-mentioned principle, the invention provides the defining method of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, as shown in Figure 1, the method comprises:

Step 11, carries out curl computing to detection wave field, obtains vector shear wave;

Step 12, calculates the direction of propagation of source wavefield and the direction of propagation of detection wave field;

Step 13, calculates the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field;

Step 14, according to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determines the symbol of scalar shear wave;

Step 15, according to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtains scalar shear wave.

In the step 11 of the inventive method, curl computing is carried out to detection wave field, when obtaining vector shear wave, the following formula of concrete employing:

$S_R=\▿\×W_R$ (formula 1)

In formula 1, S _rrepresent vector shear wave, represent curl computing, W _rrepresent detection wave field.

In the step 12 of the inventive method, calculate the direction of propagation of source wavefield and the direction of propagation of detection wave field, be specially:

In source wavefield, ask for the Poynting vector of elastic wave, obtain the direction of propagation of source wavefield;

In detection wave field, ask for the Poynting vector of elastic wave, obtain the direction of propagation of detection wave field;

Wherein, described in ask for the Poynting vector of elastic wave, specifically adopt following formula:

$E=-\left[\begin{array}{ccc}{\mathrm{\τ}}_{\mathrm{xx}}& {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{xz}}\\ {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{yy}}& {\mathrm{\τ}}_{\mathrm{yz}}\\ {\mathrm{\τ}}_{\mathrm{xz}}& {\mathrm{\τ}}_{\mathrm{yz}}& {\mathrm{\τ}}_{\mathrm{zz}}\end{array}\right]\·\left[\begin{array}{c}{v}_x\\ v_y\\ v_z\end{array}\right]$ (formula 2)

Wherein, E is the Poynting vector of elastic wave; X, y, z is have common zero point and the coordinate figure of x-axis, y-axis, z-axis in mutually orthogonal three Cartesian coordinates respectively; v _x, v _yand v _zbe respectively three components of Particle Vibration Velocity along x-axis, y-axis and z-axis in described three Cartesian coordinates; V=[v _xv _yv _z] ^tfor the vibration velocity of particle; τ _ij(i, j=x, y, z) is the components of stress at particle place;

For formula 2, if use elastic wave velocity stress equation to carry out the extrapolation of source wavefield forward and the extrapolation of detection wave field inverse time, then due to τ _ijwith the wavefield component that V is elastic wave velocity stress equation, therefore directly can obtain from wave field extrapolation process, and then try to achieve the Poynting vector of elastic wave;

For formula 2, if use elastic wave displacement equation to carry out the extrapolation of source wavefield forward and the extrapolation of detection wave field inverse time, then due to the displacement vector U=[U of particle directly can only be obtained in extrapolation process _xu _yu _z] ^t, now, τ _ijtried to achieve by particle displacement Vector operation according to following equation respectively with V:

$\left[\begin{array}{c}{\mathrm{\τ}}_{\mathrm{xx}}\\ {\mathrm{\τ}}_{\mathrm{yy}}\\ {\mathrm{\τ}}_{\mathrm{zz}}\\ {\mathrm{\τ}}_{\mathrm{yz}}\\ {\mathrm{\τ}}_{\mathrm{xz}}\\ {\mathrm{\τ}}_{\mathrm{xy}}\end{array}\right]=\left[\begin{array}{cccccc}{C}_{11}& C_{12}& C_{13}& 0& 0& 0\\ C_{21}& C_{22}& C_{23}& 0& 0& 0\\ C_{31}& C_{32}& C_{33}& 0& 0& 0\\ 0& 0& 0& C_{44}& 0& 0\\ 0& 0& 0& 0& C_{55}& 0\\ 0& 0& 0& 0& 0& C_6\end{array}\right]\·\left[\begin{array}{c}{e}_{\mathrm{xx}}\\ e_{\mathrm{yy}}\\ e_{\mathrm{zz}}\\ e_{\mathrm{yz}}\\ e_{\mathrm{xz}}\\ e_{\mathrm{xy}}\end{array}\right],$ $\left[\begin{array}{c}{v}_x\\ v_y\\ v_z\end{array}\right]=\left[\begin{array}{c}\frac{\∂U_x}{\∂t}\\ \frac{\∂U_y}{\∂t}\\ \frac{\∂U_z}{\∂t}\end{array}\right]$ (formula 3)

In formula 3, U _x, U _yand U _zbe respectively the component of particle displacement vector along dielectric model x, y and z tri-coordinate axis; C _ij(i, j=1,2 ..., 6) be dielectric resilient parameter; for the elastic strain component of medium.

The elastic wave Poynting vector computing method of above-mentioned formula 2 are applied to source wavefield, the direction of propagation represented with Poynting vector of source wavefield can be obtained, be designated as E _s; The elastic wave Poynting vector computing method of above-mentioned formula 2 are applied to detection wave field, the direction of propagation represented with Poynting vector of detection wave field can be obtained, be designated as E _r.

In the step 13 of the inventive method, calculate the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field, the following formula of concrete employing:

N ^s=E _s× E _r(formula 4)

In formula 4, n ^srepresent the vector product of the direction of propagation of source wavefield and the direction of propagation of detection wave field, n ^sdirection be the normal direction of ray plane; E _srepresent the direction of propagation of source wavefield; E _rrepresent the direction of propagation of detection wave field.

In the step 14 of the inventive method, according to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determine the symbol of scalar shear wave, specifically adopt following formula:

(formula 5)

Wherein, η ^sfor the symbol of scalar shear wave; θ ₀for S _rwith n ^sangle, and 0≤θ ₀≤ 90 °.

When the incidence of source wavefield compressional wave, the vector shear wave S of the detection wave field that the elastic wave field separation method of applying step 11 obtains _rbe compressional wave when inciding reflecting interface, the shear wave that shape transformation produces occurs at reflection spot place.As previously mentioned, detection wave field vector shear wave S _rfeature be its direction and ray plane normal direction n ^sparallel, scalar converted shear wave S therefore to be asked _rsymbol can by judging S _rwith n ^sdirection relations determine, such as both regulation in the same way for just, incorgruous for negative otherwise be 0.But due to the existence of error in numerical calculation, the detection wave field vector shear wave S calculated _rcan not with n ^sensure completely parallel, thus need to arrange the S calculated _rwith n ^sthe threshold value θ of angle ₀(0≤θ ₀≤ 90 °).Generally, that supposes to calculate works as S _rwith n ^sangle at [0, θ ₀] between or [π-θ ₀, π] between time think that the two is parallel.

In the step 15 of the inventive method, according to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtain scalar shear wave, the following formula of concrete employing:

S _r=ε η ^s| S _r| (formula 6)

In formula 6, S _rfor scalar shear wave; ε is constant, and ε=1 or-1, in order to the polarity of control and regulation scalar converted shear wave in whole zoning, such as, if wish S _rwith n ^slabel taking amount shear wave S time direction is identical _rsymbol be just, then get ε=1, if wish S _rwith n ^slabel taking amount shear wave S time direction is contrary _rsymbol be just, then get ε=-1.

The defining method of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention, also comprises: adopt following formula to be optimized the described scalar shear wave obtained:

(formula 7)

In formula 7, for the scalar shear wave after optimization, for the angle threshold value of the direction of propagation of source wavefield and the direction of propagation of detection wave field.

In theory, what above-mentioned steps 11 ~ step 15 was extracted is the scalar shear wave at reflection spot place that actual generation is reflected; And the position of reflection is there is not at other, the source wavefield direction of propagation and the detection wave field direction of propagation are identical (i.e. E in theory _sbe parallel to E _r), the n known obtained by formula in step 13 4 ^sfor null vector, the scalar shear wave symbol that formula 5 in step 14 is obtained is zero, and the scalar shear wave of the detection wave field making this place extract further is zero.This makes the scalar shear wave that only could extract detection wave field at true reflection spot place; But certainly existing due to numerical error in actual numerical value calculates, the source wavefield direction of propagation and the detection wave field direction of propagation that the locus place reflected does not occur can not ensure perfect parallelism, thus make symbol in step 14 formula 5 should be zero position there is non-zero symbol, and be insecure according to the scalar shear wave that this symbol extracts.Therefore need the scalar shear wave to above-mentioned steps 15 obtains to be optimized, specific practice is as follows: set a threshold value to the angle of the source wavefield direction of propagation and the detection wave field direction of propagation angle when the source wavefield direction of propagation and the detection wave field direction of propagation exists between or between time think that the two is parallel, judge that this some place no reflection events of this moment occurs, do not produce reflection wave, thus the scalar shear wave getting this some place of this moment be zero.

The defining method of scalar shear wave in the 3-D seismics resilient bias detection wave field that the present embodiment provides, scalar shear wave can be isolated from three-dimensional detection wave field, this scalar shear wave is that compressional wave is when inciding reflecting interface, the shear wave that shape transformation produces is there is at reflection spot place, incident wave is compressional wave, reflection wave is shear wave, is referred to as reflection converted shear wave (i.e. PS ripple); Incident wave is compressional wave, reflection wave is still compressional wave, be referred to as reflected P-wave (i.e. PP ripple), thus from three-dimensional detection wave field, isolated scalar shear wave can be used for the reflection converted shear wave imaging in 3-D seismics resilient bias, converted shear wave imaging results is reflected relative to the vector that directly application vector shear wave obtains, the physical significance of the reflection converted shear wave imaging results of scalar form is more clear and definite, is more conducive to the seismic interpretation application in later stage.

Embodiment one

The present embodiment is in conjunction with a simple three-dimensional model elasticity reverse-time migration (a kind of prestack elasticity depth migration method), the defining method of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention is described, and the application of obtained scalar shear wave is described, (coordinate that this dielectric model uses is three Cartesian coordinates to this three-dimensional tilt interfacial medium model, its coordinate axis is have common zero point and mutually orthogonal x-axis respectively, y-axis, z-axis) velocity of longitudinal wave as shown in Figure 2, this model comprises an inclined reflection interface and a horizontal reflection interface, the shear wave velocity of three layers is respectively 3000m/s from top to down, 3300m/s and 3700m/s, shear wave velocity is 0.588 times of corresponding velocity of longitudinal wave, density is constant 1000kg/m ³.

Be that input is carried out forward extrapolation to source wavefield, carried out the extrapolation of detection wave field inverse time with not separated multi-component seismic data for input with source function, obtain each moment elastic wave field;

Extract the process of scalar shear wave below for a certain moment application the present invention, the detection wave field in this moment as shown in Figure 3;

Steps A 1, application of formula 1 pair of detection wave field carries out curl computing, obtains the detection wave field vector shear wave in this moment as shown in Figure 4;

Steps A 2, application of formula 2 asks for the Poynting vector of source wavefield and detection wave field respectively, obtains the direction of propagation of source wavefield and the direction of propagation of detection wave field;

Steps A 3, application of formula 4, carries out vector product computing to the direction of propagation of source wavefield and the direction of propagation of detection wave field, obtains its vector product;

Steps A 4, application of formula 5, gets θ ₀=30 °, obtain scalar shear wave symbol;

Steps A 5, application of formula 6, in conjunction with absolute value and the scalar shear wave symbol of vector shear wave as shown in Figure 4, obtains detection wave field scalar shear wave as shown in Figure 5;

Steps A 6, to above-mentioned scalar shear wave application of formula 7, gets obtain optimization scalar shear wave as shown in Figure 6.

Each moment in single big gun migration process implements by the process of above-mentioned steps A1 ~ steps A 6, then the cross-correlation image-forming condition (formula 8) of obtained scalar shear wave application illumination compensation is carried out converted shear wave imaging to it:

$I_{\mathrm{PS}}=\underset{t=0}{\overset{t=T}{\mathrm{\Σ}}}{P}_S(x,t)\·S_R(x,t)/\underset{t=0}{\overset{t=T}{\mathrm{\Σ}}}{P}_S(x,t)\·P_S(x,t)$ (formula 8)

In formula 8, x={x, y, z} are the net points in three-dimensional tilt interfacial medium model, and x, y, z is the coordinate figure of x-axis, y-axis, z-axis in three-dimensional tilt interfacial medium model respectively, and t is the time, I _pSfor converted shear wave imaging value; P _s(x, t) is the longitudinal wave field of source wavefield, by carrying out divergence computing acquisition to source wavefield; S _rfor the scalar shear wave that application the inventive method obtains; T is the dominant record moment;

For the ease of contrast, also carried out compressional wave imaging, its image-forming condition (formula 9) is similar with above-mentioned converted shear wave image-forming condition, adopts following formula simultaneously:

$I_{\mathrm{PP}}=\underset{t=0}{\overset{t=T}{\mathrm{\Σ}}}{P}_S(x,t)\·P_R(x,t)/\underset{t=0}{\overset{t=T}{\mathrm{\Σ}}}{P}_S(x,t)\·P_S(x,t)$ (formula 9)

In formula 9, x={x, y, z} are the net points in three-dimensional tilt interfacial medium model, and x, y, z is the coordinate figure of x-axis, y-axis, z-axis in three-dimensional tilt interfacial medium model respectively, and t is the time, I _pPfor compressional wave imaging value; P _s(x, t) is the longitudinal wave field of source wavefield, by carrying out divergence computing acquisition to source wavefield; P _r(x, t) is detection wave field longitudinal wave field, by carrying out divergence computing acquisition to detection wave field.

Application said process will obtain single big gun converted shear wave imaging results and compressional wave imaging results, then to the imaging results of all big guns, (left side is PP ripple imaging results as shown in Figure 7 finally to obtain stack result, right side is PS ripple imaging results), converted shear wave imaging results is correct as shown in Figure 7, and compressional wave imaging results has good consistance.It can be said that the detection wave field scalar shear wave that bright application the present invention extracts may be used for the converted shear wave imaging in elasticity pre-stack depth migration and obtains correct imaging results.

Embodiment two

The defining method of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention is applied to and tests the converted wave imaging of certain complex model by the present embodiment, to verify the adaptability of described method to complex model, this model velocity of longitudinal wave is as shown in Figure 8 (in Fig. 8, speed unit is m/s, shear wave velocity is 0.588 times of corresponding velocity of longitudinal wave, and density is constant 1000kg/m ³), be taken from SEG/EAGE3D In A Salt-dome Model (referring to document: AminzadehFet.al., SEG/EAGE3-Dmodelingproject:2ndupdate.TheLeadingEdge, 1994,13 (9): 949 ~ 952).

Formation method adopts with the identical elasticity reverse-time migration of embodiment one, the defining method of scalar shear wave in the 3-D seismics resilient bias detection wave field that Application Example one provides in migration process, and the PS converted wave imaging result finally obtained is as shown in Fig. 9 (a); As a comparison, carried out the imaging of PP ripple, its result as shown in Figure 9 (b) simultaneously.

Known the obtained PS converted wave imaging result of composition graphs 8, Fig. 9 (a), Fig. 9 (b) is correct, and the defining method describing scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention may be used for the imaging for complex dielectrics.

Accordingly, the present invention also provides the determining device of scalar shear wave in a kind of 3-D seismics resilient bias detection wave field, and as shown in Figure 10, this device comprises:

Vector shear wave acquisition module 101, for carrying out curl computing to detection wave field, obtains vector shear wave;

Direction of propagation computing module 102, for the direction of propagation of the direction of propagation and detection wave field that calculate source wavefield;

Vector product computing module 103, for the vector product of the direction of propagation of the direction of propagation and detection wave field that calculate described source wavefield;

Symbol determination module 104, for the vector product according to the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determines the symbol of scalar shear wave;

Scalar shear wave determination module 105, for according to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtains scalar shear wave.

Preferably, described vector shear wave acquisition module 101 pairs of detection wave fields carry out curl computing, when obtaining vector shear wave, and the following formula of concrete employing:

$S_R=\▿\×W_R$

Wherein, S _rrepresent vector shear wave, represent curl computing, W _rrepresent detection wave field.

Preferably, described direction of propagation computing module 102, specifically for the Poynting vector asking for elastic wave in source wavefield, obtains the direction of propagation of source wavefield; In detection wave field, ask for the Poynting vector of elastic wave, obtain the direction of propagation of detection wave field;

Wherein, when described direction of propagation computing module 102 asks for the Poynting vector of elastic wave, the following formula of concrete employing:

$E=-\left[\begin{array}{ccc}{\mathrm{\τ}}_{\mathrm{xx}}& {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{xz}}\\ {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{yy}}& {\mathrm{\τ}}_{\mathrm{yz}}\\ {\mathrm{\τ}}_{\mathrm{xz}}& {\mathrm{\τ}}_{\mathrm{yz}}& {\mathrm{\τ}}_{\mathrm{zz}}\end{array}\right]\·\left[\begin{array}{c}{v}_x\\ v_y\\ v_z\end{array}\right]$

Wherein, E is the Poynting vector of elastic wave; X, y, z is have common zero point and the coordinate figure of x-axis, y-axis, z-axis in mutually orthogonal three Cartesian coordinates respectively; v _x, v _yand v _zbe respectively three components of Particle Vibration Velocity along x-axis, y-axis and z-axis in described three Cartesian coordinates; V=[v _xv _yv _z] ^tfor the vibration velocity of particle; τ _ij(i, j=x, y, z) is the components of stress at particle place;

When described vector product computing module 103 calculates the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field, the following formula of concrete employing:

n ^S＝E _S×E _R

Wherein, n ^srepresent the vector product of the direction of propagation of source wavefield and the direction of propagation of detection wave field; E _srepresent the direction of propagation of source wavefield; E _rrepresent the direction of propagation of detection wave field.

Preferably, described symbol determination module 104, according to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, when determining the symbol of scalar shear wave, specifically adopts following formula:

Wherein, η ^sfor the symbol of scalar shear wave; θ ₀for S _rwith n ^sangle, and 0≤θ ₀≤ 90 °.

Preferably, described scalar shear wave determination module 105, according to the symbol of the absolute value of described vector shear wave and described scalar shear wave, when obtaining scalar shear wave, specifically adopts following formula:

S _R＝ε·η ^S·|S _R|

Wherein, S _rfor scalar shear wave; ε=1 or-1.

Preferably, in the 3-D seismics resilient bias detection wave field that provides of the present embodiment, the determining device of scalar shear wave also comprises:

Optimizing module, for adopting following formula, the scalar shear wave that described scalar shear wave determination module 105 obtains being optimized:

Wherein for the scalar shear wave after optimization, for the angle threshold value of the direction of propagation of source wavefield and the direction of propagation of detection wave field.

In 3-D seismics resilient bias detection wave field provided by the invention scalar shear wave determining device in, the specific works principle of its each module and embodiment, with reference to the defining method of scalar shear wave in 3-D seismics resilient bias detection wave field provided by the invention, can repeat no more herein.

Above-described specific embodiment; object of the present invention, technical scheme and beneficial effect are further described; be understood that; the foregoing is only specific embodiments of the invention; the protection domain be not intended to limit the present invention; within the spirit and principles in the present invention all, any amendment made, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (12)

1. the defining method of scalar shear wave in 3-D seismics resilient bias detection wave field, is characterized in that, comprising:

Curl computing is carried out to detection wave field, obtains vector shear wave;

Calculate the direction of propagation of source wavefield and the direction of propagation of detection wave field;

Calculate the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field;

According to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determine the symbol of scalar shear wave;

According to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtain scalar shear wave.

2. method according to claim 1, is characterized in that, describedly carries out curl computing to detection wave field, when obtaining vector shear wave, specifically adopts following formula:

$S_R=\▿\×W_R$

Wherein, S _rrepresent vector shear wave, represent curl computing, W _rrepresent detection wave field.

3. method according to claim 2, is characterized in that, the direction of propagation of described calculating source wavefield and the direction of propagation of detection wave field, be specially:

In source wavefield, ask for the Poynting vector of elastic wave, obtain the direction of propagation of source wavefield;

In detection wave field, ask for the Poynting vector of elastic wave, obtain the direction of propagation of detection wave field;

Wherein, described in ask for the Poynting vector of elastic wave, specifically adopt following formula:

$E=-\left[\begin{array}{ccc}{\mathrm{\τ}}_{\mathrm{xx}}& {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{xz}}\\ {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{yy}}& {\mathrm{\τ}}_{\mathrm{yz}}\\ {\mathrm{\τ}}_{\mathrm{xz}}& {\mathrm{\τ}}_{\mathrm{yz}}& {\mathrm{\τ}}_{\mathrm{zz}}\end{array}\right]\·\left[\begin{array}{c}{v}_x\\ v_y\\ v_z\end{array}\right]$

Wherein, E is the Poynting vector of elastic wave; X, y, z is have common zero point and the coordinate figure of x-axis, y-axis, z-axis in mutually orthogonal three Cartesian coordinates respectively; v _x, v _yand v _zbe respectively three components of Particle Vibration Velocity along x-axis, y-axis and z-axis in described three Cartesian coordinates; V=[v _xv _yv _z] ^tfor the vibration velocity of particle; τ _ij(i, j=x, y, z) is the components of stress at particle place;

The vector product of the direction of propagation of the described source wavefield of described calculating and the direction of propagation of detection wave field, the following formula of concrete employing:

n ^S＝E _S×E _R

Wherein, n ^srepresent the vector product of the direction of propagation of source wavefield and the direction of propagation of detection wave field; E _srepresent the direction of propagation of source wavefield; E _rrepresent the direction of propagation of detection wave field.

4. method according to claim 3, is characterized in that, the described vector product according to the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determines the symbol of scalar shear wave, specifically adopts following formula:

Wherein, η ^sfor the symbol of scalar shear wave; θ ₀for S _rwith n ^sangle, and 0≤θ ₀≤ 90 °.

5. method according to claim 4, is characterized in that, the symbol of the described absolute value according to described vector shear wave and described scalar shear wave, obtains scalar shear wave, the following formula of concrete employing:

S _R＝ε·η ^S·|S _R|

Wherein, S _rfor scalar shear wave; ε=1 or-1.

6. method according to claim 5, is characterized in that, also comprises:

Following formula is adopted to be optimized the described scalar shear wave obtained:

Wherein for the scalar shear wave after optimization, for the threshold value of the angle of the direction of propagation of source wavefield and the direction of propagation of detection wave field.

7. the determining device of scalar shear wave in 3-D seismics resilient bias detection wave field, is characterized in that, comprising:

Vector shear wave acquisition module, for carrying out curl computing to detection wave field, obtains vector shear wave;

Direction of propagation computing module, for the direction of propagation of the direction of propagation and detection wave field that calculate source wavefield;

Vector product computing module, for the vector product of the direction of propagation of the direction of propagation and detection wave field that calculate described source wavefield;

Symbol determination module, for the vector product according to the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, determines the symbol of scalar shear wave;

Scalar shear wave determination module, for according to the absolute value of described vector shear wave and the symbol of described scalar shear wave, obtains scalar shear wave.

8. device according to claim 7, is characterized in that, described vector shear wave acquisition module carries out curl computing to detection wave field, when obtaining vector shear wave, and the following formula of concrete employing:

$S_R=\▿\×W_R$

Wherein, S _rrepresent vector shear wave, represent curl computing, W _rrepresent detection wave field.

9. device according to claim 8, is characterized in that, described direction of propagation computing module, specifically for the Poynting vector asking for elastic wave in source wavefield, obtains the direction of propagation of source wavefield; In detection wave field, ask for the Poynting vector of elastic wave, obtain the direction of propagation of detection wave field;

Wherein, when described direction of propagation computing module asks for the Poynting vector of elastic wave, the following formula of concrete employing:

$E=-\left[\begin{array}{ccc}{\mathrm{\τ}}_{\mathrm{xx}}& {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{xz}}\\ {\mathrm{\τ}}_{\mathrm{xy}}& {\mathrm{\τ}}_{\mathrm{yy}}& {\mathrm{\τ}}_{\mathrm{yz}}\\ {\mathrm{\τ}}_{\mathrm{xz}}& {\mathrm{\τ}}_{\mathrm{yz}}& {\mathrm{\τ}}_{\mathrm{zz}}\end{array}\right]\·\left[\begin{array}{c}{v}_x\\ v_y\\ v_z\end{array}\right]$

Wherein, E is the Poynting vector of elastic wave; X, y, z is have common zero point and the coordinate figure of x-axis, y-axis, z-axis in mutually orthogonal three Cartesian coordinates respectively; v _x, v _yand v _zbe respectively three components of Particle Vibration Velocity along x-axis, y-axis and z-axis in described three Cartesian coordinates; V=[v _xv _yv _z] ^tfor the vibration velocity of particle; τ _ij(i, j=x, y, z) is the components of stress at particle place;

When described vector product computing module calculates the vector product of the direction of propagation of described source wavefield and the direction of propagation of detection wave field, the following formula of concrete employing:

n ^S＝E _S×E _R

Wherein, n ^srepresent the vector product of the direction of propagation of source wavefield and the direction of propagation of detection wave field; E _srepresent the direction of propagation of source wavefield; E _rrepresent the direction of propagation of detection wave field.

10. device according to claim 9, it is characterized in that, described symbol determination module, according to the vector product of the direction of propagation of described vector shear wave, described source wavefield and the direction of propagation of detection wave field, when determining the symbol of scalar shear wave, specifically adopts following formula:

Wherein, η ^sfor the symbol of scalar shear wave; θ ₀for S _rwith n ^sangle, and 0≤θ ₀≤ 90 °.

11. devices according to claim 10, is characterized in that, described scalar shear wave determination module, according to the symbol of the absolute value of described vector shear wave and described scalar shear wave, when obtaining scalar shear wave, specifically adopts following formula:

S _R＝ε·η ^S·|S _R|

Wherein, S _rfor scalar shear wave; ε=1 or-1.

12. devices according to claim 11, is characterized in that, also comprise:

Optimizing module, for adopting following formula, the scalar shear wave that described scalar shear wave determination module obtains being optimized:

Wherein for the scalar shear wave after optimization, for the threshold value of the angle of the direction of propagation of source wavefield and the direction of propagation of detection wave field.