CN104360383A - Method and system for predicting seismic wave attenuation - Google Patents

Abstract

The invention provides a method for predicting seismic wave attenuation. The method comprises the following steps of calculating seismic wave attenuation and frequency dispersion of which a saturated fluid condition only contains a microscale spraying jet attenuation mechanism by using a mechanical action mechanism under a water-drainage condition and a non-water-drainage condition; calculating longitudinal and transverse wave attenuation and frequency dispersion of which a saturated fluid condition contains a microscale spraying jet attenuation mechanism and a macroscale Biot jet attenuation mechanism by using a Biot elastic wave theory; calculating seismic wave attenuation and frequency dispersion of which non-saturated fluid condition only contains microscale spraying jet and mesoscale local jet by using a periodical layered patch saturated model; calculating longitudinal wave attenuation and frequency dispersion of which the non-saturated fluid condition contains microscale spraying jet, macroscale Biot jet and mesoscale local jet by using boundary conditions of a feature unit; and predicting the seismic wave attenuation according to the various calculated attenuation and frequency dispersion results. The value of seismic wave attenuation predicted by using the seismic wave attenuation and frequency dispersion is close to a true value.

Description

A kind of method and system of seismic wave attenuation prediction

Technical field

The application relates to seismic event prediction field, the particularly method and system predicted of a kind of seismic wave attenuation.

Background technology

In recent years, the decay that people produce in the complicated pore fluid communication process in underground for seismic event is consistent with frequency dispersion research constant, and achieves abundant achievement in research.

But do not consider hard hole in existing seismic wave attenuation forecasting research and mix crack and the situation of depositing, the authenticity predicted the outcome has much room for improvement simultaneously.

Therefore, the authenticity how effectively improving prediction seismic wave attenuation is the current technical issues that need to address of those skilled in the art.

Summary of the invention

Technical problems to be solved in this application are to provide the method and system of a kind of seismic wave attenuation prediction, solve the problem that the authenticity that predicts the outcome in prior art has much room for improvement.Its concrete scheme is as follows:

A method for seismic wave attenuation prediction, the method comprises:

In conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism;

In conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot;

In conjunction with periodicity stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream;

In conjunction with the boundary condition of feature unit, calculate attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream;

According to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

Above-mentioned method, preferably, described in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation and only comprise containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion:

Calculate fluid in mixed type crack and squeeze spray and the pore-fluid pressure that causes;

The bulk modulus of saturated rock is calculated according to described pore-fluid pressure;

According to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

Above-mentioned method, preferably, described in conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation and flow the wave attenuation in length and breadth of attenuating mechanism containing micro-scale injection stream and macro-scale Biot and frequency dispersion comprises:

According to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculate the Time Migration of Elastic Wave Equation containing hole, mixed type crack;

Decoupling zero is carried out to described Time Migration of Elastic Wave Equation and obtains compressional wave equation and shear wave equation;

According to described compressional wave equation and described shear wave equation, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

Above-mentioned method, preferably, described combination is stratiform patchy saturation periodically, calculates unsaturation fluid situations and only comprises containing the seismic wave attenuation of micro-scale injection stream and meso-scale local stream and frequency dispersion:

According to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtain the ground roll modulus that frequently flattens;

Unsaturation fluid situations is calculated only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream and medium measure local stream according to the described frequency ground roll modulus that flattens.

Above-mentioned method, preferably, the described boundary condition in conjunction with feature unit, calculates unsaturation fluid situations and comprises containing the attenuation of P-wave of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream and frequency dispersion:

According to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculate upper and lower solid displacement;

Body according to described solid displacement calculation feature unit becomes;

The definition of bulk modulus is utilized to calculate the ground roll modulus that frequently flattens;

Flattening according to described frequency, ground roll modulus calculating unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot flows and the quantitative expression of the seismic wave attenuation of medium measure local stream attenuating mechanism;

Utilize the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, calculate unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

Above-mentioned method, preferably, described Biot elastic wave prorogation theory comprises:

The mass conservation condition of elastic constitutive model equation, nonlinear New-tonian law and pipeline stream.

A system for seismic wave attenuation prediction, this system comprises:

First computing unit: in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism;

Second computing unit: in conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot;

3rd computing unit: for combining periodically stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream;

4th computing unit: for the boundary condition in conjunction with feature unit, calculates attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream;

Predicting unit: for according to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

Above-mentioned system, preferably, described first computing unit comprises:

5th computing unit: squeeze spray and the pore-fluid pressure that causes for calculating fluid in mixed type crack;

6th computing unit: for calculating the bulk modulus of saturated rock according to described pore-fluid pressure;

7th computing unit: for according to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

Above-mentioned system, preferably, described second computing unit comprises:

8th computing unit: for according to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculates the Time Migration of Elastic Wave Equation containing hole, mixed type crack;

First solves unit: obtain compressional wave equation and shear wave equation for carrying out decoupling zero to described Time Migration of Elastic Wave Equation;

9th computing unit: for according to described compressional wave equation and described shear wave equation, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

Above-mentioned system, preferably, described 3rd computing unit comprises:

Second solves unit: for according to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtain the ground roll modulus that frequently flattens;

Tenth computing unit: the seismic wave attenuation and the frequency dispersion that only contain micro-scale injection stream and medium measure local stream for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency.

Above-mentioned system, preferably, described 4th computing unit comprises:

11 computing unit: for according to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculates upper and lower solid displacement;

12 computing unit: become for the body according to described solid displacement calculation feature unit;

13 computing unit: calculate the ground roll modulus that frequently flattens for utilizing the definition of bulk modulus;

14 computing unit: the quantitative expression containing the seismic wave attenuation of micro-scale injection stream, macro-scale Biot stream and medium measure local stream attenuating mechanism for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency;

3rd solves unit: for utilizing the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, obtains unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream

In the method and system of a kind of seismic wave attenuation prediction that the application provides, for underground containing fluid hole complex dielectrics, on the basis considering circular hard hole in hole, introduce mixed type crack.In conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism; In conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot; In conjunction with periodicity stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream; On this basis, in turn introduce the boundary condition of feature unit, calculate attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream; These seismic wave attenuation described in utilization and frequency dispersion carry out seismic wave attenuation prediction more close to actual value.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme in the embodiment of the present application, 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 application, 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 process flow diagram of the embodiment of the method 1 of a kind of seismic wave attenuation prediction of the application;

Fig. 2 is the process flow diagram of the embodiment of the method 2 of a kind of seismic wave attenuation prediction of the application;

Fig. 3 is the process flow diagram of the embodiment of the method 3 of a kind of seismic wave attenuation prediction of the application;

Fig. 4 is the process flow diagram of the embodiment of the method 4 of a kind of seismic wave attenuation prediction of the application;

Fig. 5 is the process flow diagram of the embodiment of the method 5 of a kind of seismic wave attenuation prediction of the application;

Fig. 6 is the process flow diagram of the method embody rule of a kind of seismic wave attenuation prediction of the application;

Fig. 7 is the another process flow diagram of the method embody rule of a kind of seismic wave attenuation prediction of the application;

Fig. 8 is the structural representation of the system embodiment 1 of a kind of seismic wave attenuation prediction of the application;

Fig. 9 is the structural representation of the system embodiment 2 of a kind of seismic wave attenuation prediction of the application;

Figure 10 is the structural representation of the system embodiment 3 of a kind of seismic wave attenuation prediction of the application;

Figure 11 is the structural representation of the system embodiment 4 of a kind of seismic wave attenuation prediction of the application;

Figure 12 is the structural representation of the system embodiment 5 of a kind of seismic wave attenuation prediction of the application.

Embodiment

Core of the present invention is to provide the method and system of a kind of seismic wave attenuation prediction, solves the problem that the authenticity that predicts the outcome in prior art has much room for improvement.

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

With reference to figure 1, show the process flow diagram of the embodiment of the method 1 of a kind of seismic wave attenuation prediction of the application, can comprise the following steps:

Step S101: in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculates saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism.

Underground complexity is varied containing the pore morpholohy of fluid pore media, considers, not only containing the hard hole be interconnected in hole, to also have the crack of two kinds dissimilar (Coin shape, pinching types).Under prerequisite containing circular hard hole in hole, consider situation when two kinds of dissimilar crevice space coexist, a kind of is the Coin shape crack be interconnected with around hard hole, and another kind is the pinching type crack that one end is closed.Truth under making built petrophysical model more closely, the seismic wave attenuation of prediction is more close to actual value.

When the hard hole of circle considered in space be uniformly distributed and be interconnected time, the Hydrodynamics Mechanism of effect is the injection stream of " macro-scale ", and size is suitable with seismic event wavelength; When the two kinds of dissimilar cracks considered are micro-scale, the Hydrodynamics Mechanism of effect be that " injection stream " is machine-processed, size and particle size sizableness; When the feature unit considered is medium measure, the Hydrodynamics Mechanism of effect be that " local stream " is machine-processed, and its size is much larger than particle size and be less than earthquake wavelength.

Step S102: in conjunction with Biot elastic wave prorogation theory, calculates saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

Described Biot elastic wave prorogation theory comprises: the mass conservation condition of elastic constitutive model equation, nonlinear New-tonian law and pipeline stream.

Step S103: combine periodically stratiform patchy saturation, calculates seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream.

Described periodicity stratiform patchy saturation is the stratum cycle stacked distribution containing different fluid type, laterally infinitely extends, and the medium of every layer is for containing hole, mixed type fissuted medium.

Step S104: in conjunction with the boundary condition of feature unit, calculates attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

Described feature unit chooses the half of levels thickness in periodicity stratiform patchy saturation, comprises three interfaces, is interface, top, interphase and bottom boundary respectively.

Step S105: according to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

The application contains fluid hole complex dielectrics for underground, on the basis considering circular hard hole in hole, introduce two kinds of dissimilar fractured zones situations, comprise the closed pinching type crack in the Coin shape crack that is communicated with around hard hole and one end, hole crack hydrodynamic pressure when utilizing hole and crack and deposit, dopes the seismic wave attenuation in saturated fluid situation and frequency dispersion.On this basis, in turn introduce the characteristic boundary condition of medium measure operate under unsaturated conditions, calculate the seismic wave attenuation containing hole, mixed type fissuted medium earthquake rock and frequency dispersion, these seismic wave attenuation described in utilization and frequency dispersion carry out seismic wave attenuation prediction more close to actual value.

With reference to figure 2, show the process flow diagram of the embodiment of the method 2 of a kind of seismic wave attenuation prediction of the application, described in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation and only comprise containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion:

Step S201: calculate fluid in mixed type crack and squeeze spray and the pore-fluid pressure that causes.

Due to the effect of extraneous load, these two kinds of cracks are made easily to make in the hard hole of direction of flow circle by compression, thus produce jet flow phenomenon, suppose that now displacement of fluid is equal with solid displacement in hard hole, assumed condition and Gassmannn condition similar, then can obtain because fluid in mixing crack squeezes spray and the pore-fluid pressure quantitative expression that causes.

Step S202: the bulk modulus calculating saturated rock according to described pore-fluid pressure.

Step S203: according to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculates saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

Step S201 and step S202 only sets up physical model containing the earthquake rock under micro-scale injection stream attenuating mechanism condition to described saturated fluid situation, step S203 solves the physical model of described foundation, obtains described saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

With reference to figure 3, show the process flow diagram of the embodiment of the method 3 of a kind of seismic wave attenuation prediction of the application, described in conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation and flow the wave attenuation in length and breadth of attenuating mechanism containing micro-scale injection stream and macro-scale Biot and frequency dispersion comprises:

Step S301: according to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculates the Time Migration of Elastic Wave Equation containing hole, mixed type crack.

Step S302: decoupling zero is carried out to described Time Migration of Elastic Wave Equation and obtains compressional wave equation and shear wave equation.

Step S303: according to described compressional wave equation and described shear wave equation, calculates saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

Step S301 and step S302 sets up physical model to the earthquake rock that described saturated fluid situation flows under attenuating mechanism condition containing micro-scale injection stream and macro-scale Biot, step S203 solves the physical model of described foundation, obtains described saturated fluid situation containing the seismic wave attenuation under micro-scale injection stream and macro-scale Biot stream attenuating mechanism condition and frequency dispersion.

With reference to figure 4, show the process flow diagram of the embodiment of the method 4 of a kind of seismic wave attenuation prediction of the application, described combination is stratiform patchy saturation periodically, calculates unsaturation fluid situations and only comprises containing the seismic wave attenuation of micro-scale injection stream and meso-scale local stream and frequency dispersion:

Step S401: according to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtains the ground roll modulus that frequently flattens.

According to described pore-fluid pressure, then combine and that the cause local stream attenuating mechanism of medium measure different by bilevel hydrodynamic pressure in periodicity stratiform patchy saturation, obtain described frequency and to flatten ground roll modulus.

Step S402: calculate unsaturation fluid situations only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream and medium measure local stream according to the described frequency ground roll modulus that flattens.

With reference to figure 5, show the process flow diagram of the embodiment of the method 5 of a kind of seismic wave attenuation prediction of the application, the described boundary condition in conjunction with feature unit, calculates unsaturation fluid situations and comprises containing the attenuation of P-wave of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream and frequency dispersion:

Step S501: according to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculates upper and lower solid displacement.

Step S502: the body according to described solid displacement calculation feature unit becomes.

Step S503: utilize the definition of bulk modulus to calculate the ground roll modulus that frequently flattens.

Step S504: flattening according to described frequency, ground roll modulus calculating unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot flows and the quantitative expression of the seismic wave attenuation of medium measure local stream attenuating mechanism.

Step S505: utilize the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, calculates unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

Step S501 to step S504 only sets up physical model containing the earthquake rock under micro-scale injection stream, macro-scale Biot stream and meso-scale local stream attenuating mechanism condition to described unsaturated flow concrete conditions in the establishment of a specific crime, step S505 solves the physical model of described foundation, obtains described unsaturated flow concrete conditions in the establishment of a specific crime only containing the attenuation of P-wave under micro-scale injection stream, macro-scale Biot stream and meso-scale local stream attenuating mechanism condition and frequency dispersion.

This application provides a kind of seismic wave attenuation Forecasting Methodology.Considering Coin shape, on basis that pinching type crack affects pore-fluid pressure, construct the propagation equation containing mixing crack, pore media during saturated fluid under Biot theoretical frame, and obtain rock volume modulus when only considering saturated fluid in the situation of dissimilar crack further.Consider again the heteropical impact of the meso-scale of two-phase fluid in hole subsequently on this basis, in conjunction with the periodicity stratified model that forefathers set up, mixing crack, porous materials models is contained under constructing unsaturation situation, try to achieve the plane wave modulus containing dissimilar crack, pore media in unsaturation situation, and the seismic wave attenuation of this model of computational prediction and frequency dispersion.

With reference to figure 6, show the process flow diagram of the method embody rule of a kind of seismic wave attenuation prediction of the application, construction method containing hole, mixed type fissuted medium petrophysical model is: for underground containing hole fluid media (medium), under prerequisite containing circular hard hole in hole, consider situation when two kinds of dissimilar crevice space coexist, be the Coin shape crack be interconnected with around hard hole, another kind is the pinching type crack that one end is closed.First, by research containing hole, mixed type fissuted medium average fluid pressure, obtain the bulk modulus of this model, and then ask for its saturated fluid situation only containing the seismic wave attenuation that micro-scale " injection stream " affects, secondly, further consider Biot attenuation mechanism of seismic wave, calculate seismic wave attenuation and frequency dispersion that this model saturated fluid situation only contains micro-scale " injection stream " and macro-scale " Biot stream ".Subsequently, utilize periodically stratiform patchy saturation to obtain containing the plane wave modulus under the operate under unsaturated conditions of hole, mixed type fissuted medium petrophysical model, seek out only containing the seismic wave attenuation under micro-scale " injection stream " and medium measure " local stream " situation and frequency dispersion.Finally, the seismic wave attenuation and the frequency dispersion that only contain micro-scale " injection stream ", meso-scale " local stream " and macro-scale " Biot stream " situation under Biot attenuating mechanism calculates unsaturated flow concrete conditions in the establishment of a specific crime is introduced.

With reference to figure 7, show the another process flow diagram of the method embody rule of a kind of seismic wave attenuation of the application prediction, build the concrete steps of described physical model as shown in the technical scheme process flow diagram of Fig. 7, comprise: containing hole, mixed type fissuted medium petrophysical model method for building up is: containing hole fluid media (medium) elastic constitutive model equation in saturated fluid situation, on the basis of the mass conservation of nonlinear New-tonian law and pipeline stream, consider the mass conservation of " injection stream " caused containing mixed type crack, hole is contained under setting up saturated fluid situation, the Time Migration of Elastic Wave Equation of mixed type fissuted medium petrophysical model.Further consider the boundary condition of unsaturation fluid situations medium measure feature unit, under obtaining unsaturation fluid situations, contain the quantificational expression formula of hole, mixed type fissuted medium seismic wave attenuation and frequency dispersion.

The concrete steps realizing seismic wave attenuation prediction in embody rule are:

Step S601: extraneous this model of load effect, these two kinds of cracks easily make in the hard hole of direction of flow circle by compression, thus produce jet flow phenomenon, suppose that now displacement of fluid is equal with solid displacement in hard hole, assumed condition and Gassmannn condition similar, then can obtain because fluid in mixing crack squeezes spray and the pore-fluid pressure quantitative expression that causes.

Step S602: that asks for according to step 1 squeezes jet flow by fluid in crack and the pore-fluid pressure caused, in conjunction with the mechanical function mechanism under draining and non-drainage condition, ask for this model saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

When we only consider the jetting action in crack, namely in hard hole, displacement of fluid is equal with solid displacement, and the condition of assumed condition and Gassmann equation is similar, then the hydrodynamic pressure now caused due to the crowded spray of fluid in crack is:

$P_f=-(\mathrm{\α}\▿\·\stackrel{v}{u}+{\mathrm{\φq}}_1+{\mathrm{\φq}}_2)/\mathrm{\β}---\left(1\right)$

Now the bulk modulus of saturated rock is:

$K_{\mathrm{sq}}=K_d+{\mathrm{\α}}^2/(\mathrm{\β}+S_1^{+}\left(\mathrm{\ω}\right)+S_2^{+}\left(\mathrm{\ω}\right))---\left(2\right)$

Wherein, with expression time simple harmonic quantity system is e ^iwtsupposed premise under the result of deriving, upper target sign only can affect the imaginary part information of complex modulus, ensures to calculate seismic wave attenuation value for needed for just, makes the physical significance that it is more realistic.

$S_1^m\left(\mathrm{\ω}\right)=8\mathrm{\π\ϵ}(1-v_G)f\left({\mathrm{\ζ}}^{\±}\right)\frac{(1/K_d-1/K_s)/(1/K_d-1/K_G)-f\left({\mathrm{\ζ}}^{\±}\right)}{3\mathrm{\μ}\{1+4(1-v_G)[1-f\left({\mathrm{\ζ}}^{\±}\right)]/3\mathrm{\μ\γ}\}}---\left(3\right)$

Wherein, f (ζ ^±)=2J ₁(ζ ^±)/ζ ^±j ₀(ζ ^±), ${\mathrm{\ζ}}^{\±}=\sqrt{\±3\mathrm{im\η}/{\mathrm{\γ}}^2{K}_f},$ $\mathrm{\ϵ}={\mathrm{NR}}_a^3/V,$ γ=h/2R _a, J ₁, J ₀for single order and zero Bessel function, ν _g, K _gfor Poisson ratio and the bulk modulus of saturated rock under zero-frequency condition, ε is fracture density, and γ is Crack aspect ratio, and N is the number in crack in the rock of volume V, and h is crack thickness, R _afor Coin shape crack radius.

$S_2^m\left(\mathrm{\ω}\right)=\frac{8\mathrm{\ϵ}(1-v_G){(1+{\mathrm{\λ}}_T)}^3}{3\mathrm{\μ}}\frac{\left(\frac{1/K_G-1/K_s}{1/K_d-1/K_G}\right)M}{1m\frac{3\mathrm{iw\η}(1+2{\mathrm{\λ}}_T)}{2K_f{\mathrm{\λ}}_T{\mathrm{\γ}}^2}[1+\frac{4(1-v_G)K_f{(1+{\mathrm{\λ}}_T)}^3}{3\mathrm{\π\μ}(1+2{\mathrm{\λ}}_T)}M]}---\left(4\right)$

Wherein, $M=1+\frac{4-5v_G}{2(7-5v_G)}\frac{{\mathrm{\λ}}_T^3}{{(1+{\mathrm{\λ}}_T)}^3}+\frac{9}{2(7-5v_G)}\frac{{\mathrm{\λ}}_T^5}{{(1+{\mathrm{\λ}}_T)}^5},$ ${\mathrm{\λ}}_T={\left(\frac{3\mathrm{\φ}}{4\mathrm{\π\ϵ}}\right)}^{1/3},$ ε＝Na ³/V，γ＝h/2a。

Wherein, N is the number in crack in the rock of volume V, and h is crack thickness, and a is the length in pinching type crack.

In like manner can contain the bulk modulus of the saturated rock under hole, Coin shape and pinching type fissuted medium injection stream condition and its seismic wave attenuation and frequency dispersion:

$K_{\mathrm{sq}\_c1}=K_d+{\mathrm{\α}}^2/(\mathrm{\β}+S_1^{+}\left(\mathrm{\ω}\right))---\left(5\right)$

$K_{\mathrm{sq}\_c2}=K_d+{\mathrm{\α}}^2/(\mathrm{\β}+S_2^{+}\left(\mathrm{\ω}\right))---\left(6\right)$

$V_p\left(\mathrm{\ω}\right)=\mathrm{real}\sqrt{\frac{K+4\mathrm{\μ}/3}{\stackrel{\‾}{\mathrm{\ρ}}}}---\left(7\right)$

$\frac{1}{Q}=\frac{\mathrm{imag}(K+4\mathrm{\μ}/3)}{\mathrm{real}(K+4\mathrm{\μ}/3)}---\left(8\right)$

Wherein, for being full of single fluid medium, equivalent density for being full of two-phase fluid medium, equivalent density $\stackrel{\‾}{\mathrm{\ρ}}=\underset{j=a}{\overset{b}{\mathrm{\Σ}}}\left[((1-{\mathrm{\φ}}_j){\mathrm{\ρ}}_s^j+{\mathrm{\φ}}_a{\mathrm{\ρ}}_f^j)(d_j/(d_a+d_b))\right].$

Saturated fluid condition can be obtained by formula (2), (7) and (8) and only contain hole, mixed type fissuted medium seismic wave attenuation and frequency dispersion containing in micro-scale injection stream attenuating mechanism situation.When in pore media containing two kinds of dissimilar cracks time, can there are two peak values in its seismic wave attenuation curve, velocity dispersion occurs in two different frequency ranges, and this is because the decay dominant frequency difference of the injection attenuating mechanism in dissimilar crack causes.In addition, due to containing large than in single type crack, pore media of mixing crack, fracture density in pore media, the dry Modulus of Rocks value calculated is relatively little, so its bulk velocity is also relatively low.

Step S603: the pore-fluid pressure obtained according to step 1, in conjunction with the mass conservation condition of the elastic constitutive model equation under Biot elastic wave prorogation theory framework, nonlinear New-tonian law and pipeline stream, obtain the Time Migration of Elastic Wave Equation containing hole, mixed type crack, this equation is carried out to compressional wave equation and the shear wave equation of this model that decoupling zero is asked, finally calculate this model saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

During extraneous load effect, mixed type crack easily makes in the hard hole of direction of flow circle by compression, thus generation jet flow phenomenon, then now under Biot elastic wave prorogation theory in hole hydrodynamic pressure be:

$P_f=-(\mathrm{\α}\▿\·\stackrel{v}{u}+\▿\·\stackrel{v}{w}+\mathrm{\φ}{q}_1+{\mathrm{\φq}}_2)/\mathrm{\β}---\left(9\right)$

Be similar to Tang (2011), (2012) set up containing hole, fissuted medium wave equation, utilize hydrodynamic pressure equation (9) can obtain the Time Migration of Elastic Wave Equation of apertures, mixed type crazing medium:

$\begin{array}{c}{\mathrm{\μ}\▿}^2\stackrel{v}{u}+\▿((P-\mathrm{\μ})\▿\·\stackrel{v}{u}+Q\▿\·\stackrel{v}{U})=\frac{{\∂}^2}{{\∂t}^2}({\mathrm{\ρ}}_{11}\stackrel{v}{u}+{\mathrm{\ρ}}_{12}\stackrel{v}{U})+b\frac{\∂}{\∂t}(\stackrel{v}{u}-\stackrel{v}{U})\\ \▿(Q\▿\·\stackrel{v}{u}+R\▿\·\stackrel{v}{U})=\frac{{\∂}^2}{{\∂t}^2}({\mathrm{\ρ}}_{12}\stackrel{v}{u}+{\mathrm{\ρ}}_{22}\stackrel{v}{U})-b\frac{\∂}{\∂t}(\stackrel{v}{u}-\stackrel{v}{U})\end{array}---\left(10\right)$

In formula, ρ ₁₁+ ρ ₁₂=(1-φ) ρ _s, ρ ₁₂+ ρ ₂₂=φ ρ _f, $b={\mathrm{\η\φ}}^2\sqrt{1+\mathrm{i\ω}/2{\mathrm{\ω}}_B}/\mathrm{\κ},$

Wherein, $P=K_d+4\mathrm{\μ}/3+{(\mathrm{\α}-\mathrm{\φ})}^2/[K_a+S_1^{+}\left(\mathrm{\ω}\right)+S_2^{+}\left(\mathrm{\ω}\right)]---\left(11\right)$

$Q=\mathrm{\φ}(\mathrm{\α}-\mathrm{\φ})/[K_a+S_1^{+}\left(\mathrm{\ω}\right)+S_2^{+}\left(\mathrm{\ω}\right)]---\left(12\right)$

$R={\mathrm{\φ}}^2/[K_a+S_1^{+}\left(\mathrm{\ω}\right)+S_2^{+}\left(\mathrm{\ω}\right)]---\left(13\right)$

In formula, $K_a=(\mathrm{\α}-\mathrm{\φ})/K_s+\mathrm{\φ}/K_f.$

Wherein, subscript t, x representative is to time and directional derivative.Subscript s, f represent solid phase, stream phase respectively.ρ is density, for the structure factor of pore media, for spherical solid particles r=0.5, η, κ are respectively the coefficient of viscosity and the permeability of fluid.ω is circular frequency, ω _bfor Biot characteristic frequency.α is Biot coefficient, and μ is the modulus of shearing of skeleton.The volume of dry rock, modulus of shearing utilize the proper theory of the Biot phase of Thomsen to ask for.

Solved by the decoupling zero of formula (10) wave equation, can obtain under saturated fluid condition only flows attenuating mechanism situation containing micro-scale injection stream and macro-scale Biot and decay and frequency dispersion containing hole, mixed type fissuted medium speed, compressional wave and shear wave.Known, the absorption parameter curve of fast Slow P-wave and shear wave has multiple damping peak, its amplitude and frequency band range are also not quite similar, fast Slow P-wave and horizontal wave propagation velocity are with the frequency dispersion degree of frequency change and frequency band range also corresponding difference, this is because the injection attenuating mechanism in dissimilar crack and the mechanism process difference of Biot attenuating mechanism cause, for the absorption parameter of fast compressional wave and frequency dispersion rate curve, by with containing hole, Coin shape fissuted medium and containing hole, absorption parameter curve comparison in pinching type fissuted medium, damping peak indicated by Biot represents the attenuation peak produced by macroscopical Biot attenuation mechanism.By with containing hole, Coin shape fissuted medium with contrast containing hole, frequency dispersion rate curve in pinching type fissuted medium, the frequency dispersion of the different frequency range of the known frequency dispersion speed containing hole, the fast compressional wave of mixed type fissuted medium is also corresponding to be caused by different attenuations is machine-processed.

Compare with the frequency dispersion rate curve of the Slow P-wave containing hole, pinching type fissuted medium with containing hole, Coin shape fissuted medium, frequency dispersion speed containing the Slow P-wave of hole, mixed type fissuted medium is relatively low, and the frequency band range of differential declines mechanism of action cannot be distinguished, the result of a just combined action.And it is similar with the transform characteristics compressional wave fast with it of frequency containing hole, the shear wave absorption parameter of mixed type fissuted medium and frequency dispersion speed.

Step S604: that asks for according to step 1 squeezes spray and the pore-fluid pressure that causes by fluid in mixing crack, the local stream attenuating mechanism of the medium measure caused in conjunction with hydrodynamic pressure difference bilevel in periodicity stratiform patchy saturation, the frequency obtaining this model flattens ground roll modulus, and then asks for this model in unsaturation fluid situations only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream and medium measure local stream.

In periodicity stratiform patch saturated media model during the unsaturation fluid that White proposes, be full of gas medium a layer and be full of fluid media (medium) b layer and be alternately arranged, every layer of transverse direction infinitely extends and only containing the hard hole be interconnected, thickness is respectively 2d _a, 2d _b.Only considered the fluid flowing of the meso-scale caused due to bilevel hydrodynamic pressure difference at first, for low cut model, when introducing containing hole, mixed type fissuted medium structure in the pore media of every layer, then utilize the White formula process of deriving in hydrodynamic pressure formula (6) and Carcione, the plane wave modulus of the compressional wave of periodically stratiform apertures gap, mixed type fissuted medium model can be obtained:

$E={[\frac{1}{E_0}+\frac{2{(r_a-r_b)}^2}{\mathrm{i\ω}(d_a+d_b)(I_a+I_b)}]}^{-1}---\left(14\right)$

In formula, $E_0^{-1}=\underset{j=a}{\overset{b}{\mathrm{\Σ}}}{d}_j/\left[(d_a+d_b)E_j\right],$ $E_j=K_{\mathrm{sq}}^j+3{\mathrm{\μ}}_j/4,$ $r_j=\frac{{\mathrm{\α}}_j}{({\mathrm{\β}}_j+S_1^j\left(\mathrm{\ω}\right)+S_2^j\left(\mathrm{\ω}\right))E_j},$ $I_j=\frac{{\mathrm{\η}}_j}{k_j{s}_j}\coth \left(\frac{s_j{d}_j}{2}\right),$ $s_j^2=\frac{{\mathrm{i\ω\η}}_j}{k_j{K}_E^j},$ $K_E^j=\frac{E_d^j}{({\mathrm{\β}}_j+{\left(S_1^{+}\left(\mathrm{\ω}\right)\right)}_j+{\left(S_2^{+}\left(\mathrm{\ω}\right)\right)}_j)E_j},$ $E_d^j=K_d^j+\frac{3{\mathrm{\μ}}_j}{4}.$ Wherein, the subscript of parameter or subscript j=a, b, represent the elastic parameter of levels.

Coefficient r in formula (14) _j, during for following formula, other parameter constants, can obtain under low frequency condition containing Coin shape and the plane wave modulus containing pinching type crack, porous materials models.

$r_j=\frac{{\mathrm{\α}}_j}{({\mathrm{\β}}_j+{\left(S_1^{+}\left(\mathrm{\ω}\right)\right)}_j)E_j},r_j=\frac{{\mathrm{\α}}_j}{({\mathrm{\β}}_j+{\left(S_2^{+}\left(\mathrm{\ω}\right)\right)}_j)E_j}---\left(15\right)$

$K_E^j=\frac{E_d^j}{({\mathrm{\β}}_j+{\left(S_1^{+}\left(\mathrm{\ω}\right)\right)}_j)E_j},K_E^j=\frac{E_d^j}{({\mathrm{\β}}_j+{\left(S_2^{+}\left(\mathrm{\ω}\right)\right)}_j)E_j}---\left(16\right)$

Frequency dispersion speed under different model and absorption parameter can utilize multiple bulk modulus to ask for:

$V_p\left(\mathrm{\ω}\right)=\mathrm{real}\sqrt{\frac{E}{\stackrel{\‾}{\mathrm{\ρ}}}}---\left(17\right)$

$\frac{1}{Q}=\frac{\mathrm{imag}\left(E\right)}{\mathrm{real}\left(E\right)}---\left(18\right)$

Unsaturated flow concrete conditions in the establishment of a specific crime can be obtained only contain hole, mixed type fissuted medium attenuation of P-wave and frequency dispersion containing under micro-scale injection stream and medium measure local stream attenuating mechanism situation by formula (14), (17), (18), known, containing the multi-peaks phenomenon of the compressional wave absorption parameter curve of hole, mixed type fissuted medium petrophysical model in unsaturation situation, its velocity of longitudinal wave also can accordingly at multiple frequency band range generation dispersion phenomenon, and this is the result due to differential declines machining function.

Step S605: the compressional wave equation obtained according to step 3, utilize the boundary condition of feature unit, ask for the solid displacement that it is upper and lower, and then the body of the feature unit asked becomes, the frequency utilizing the definition of bulk modulus to ask for this model flattens ground roll modulus, finally calculates the quantitative expression asked for this model and contain the seismic wave attenuation of micro-scale injection stream, macro-scale Biot stream and medium measure local stream attenuating mechanism in unsaturation fluid situations.

The compressional wave equation of more rigorous Time Migration of Elastic Wave Equation (10) is utilized to solve the plane wave modulus under this model Whole frequency band condition as the propagation equation of every layer of medium in periodicity stratiform apertures gap, mixing fissuted medium model, then attenuating mechanism now not only has the crowded sedimentation exhalation in two kinds of micro-scale cracks, the fluid flow function of the meso-scale between dissimilar fluid, also has macroscopical relative motion effect between fluid and skeleton.The one dimension compressional wave equation of Time Migration of Elastic Wave Equation (10) is:

ρ ₁₁u _tt+ρ ₁₂U _tt+b(u _t-U _t)＝Pu _xx+QU _xx

ρ ₁₂u _tt+ρ ₂₂U _tt-b(u _t-U _t)＝Qu _xx+RU _xx(19)

The method of Concerning With Fast-slow Waves decoupling zero is utilized to solve unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

Hole, mixed type fissuted medium attenuation of P-wave and frequency dispersion is contained by solving formula (19) decoupling zero can obtain under unsaturated flow concrete conditions in the establishment of a specific crime only flows attenuating mechanism situation containing micro-scale injection stream, medium measure local stream and macro-scale Biot, known, at high band, the decay of compressional wave raises suddenly and suddenly declines with velocity of longitudinal wave, this is because periodicity stratified model used has own limitations, produce resonance effect when the thickness on seismic event wavelength and stratum is suitable, the energy of seismic event passes not go down and causes.

Corresponding with the method that a kind of seismic wave attenuation of above-mentioned the application Forecasting Methodology embodiment 1 provides, see Fig. 8, present invention also provides a kind of seismic wave attenuation prognoses system embodiment 1, in the present embodiment, this system comprises:

First computing unit 701: in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism.

Second computing unit 702: in conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

3rd computing unit 703: for combining periodically stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream.

4th computing unit 704: for the boundary condition in conjunction with feature unit, calculates attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

Predicting unit 705: for according to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

See Fig. 9, present invention also provides a kind of structural representation of seismic wave attenuation prognoses system embodiment 2, in the present embodiment, described first computing unit 701 comprises:

5th computing unit 801: squeeze spray and the pore-fluid pressure that causes for calculating fluid in mixed type crack.

6th computing unit 802: for calculating the bulk modulus of saturated rock according to described pore-fluid pressure.

7th computing unit 803: for according to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

See Figure 10, present invention also provides a kind of structural representation of seismic wave attenuation prognoses system embodiment 3, in the present embodiment, described second computing unit 702 comprises:

8th computing unit 901: for according to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculates the Time Migration of Elastic Wave Equation containing hole, mixed type crack.

First solves unit 902: obtain compressional wave equation and shear wave equation for carrying out decoupling zero to described Time Migration of Elastic Wave Equation.

9th computing unit 903: for according to described compressional wave equation and described shear wave equation, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

See Figure 11, present invention also provides a kind of structural representation of seismic wave attenuation prognoses system embodiment 4, in the present embodiment, described 3rd computing unit 703 comprises:

Second solves unit 1001: for according to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtain the ground roll modulus that frequently flattens.

Tenth computing unit 1002: the seismic wave attenuation and the frequency dispersion that only contain micro-scale injection stream and medium measure local stream for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency.

See Figure 12, present invention also provides a kind of structural representation of seismic wave attenuation prognoses system embodiment 5, in the present embodiment, described 4th computing unit 704 comprises:

11 computing unit 1101: for according to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculates upper and lower solid displacement.

12 computing unit 1102: become for the body according to described solid displacement calculation feature unit.

13 computing unit 1103: calculate the ground roll modulus that frequently flattens for utilizing the definition of bulk modulus.

14 computing unit 1104: the quantitative expression containing the seismic wave attenuation of micro-scale injection stream, macro-scale Biot stream and medium measure local stream attenuating mechanism for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency.

3rd solves unit 1105: for utilizing the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, obtains unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

In sum, this application provides the method and system of a kind of seismic wave attenuation prediction, considering Coin shape, on basis that pinching type crack affects pore-fluid pressure, construct the propagation equation containing mixing crack, pore media during saturated fluid under Biot theoretical frame, and obtain rock volume modulus when only considering saturated fluid in the situation of dissimilar crack further.Consider again the heteropical impact of the meso-scale of two-phase fluid in hole subsequently on this basis, in conjunction with the periodicity stratified model that forefathers set up, mixing crack, porous materials models is contained under constructing unsaturation situation, try to achieve the plane wave modulus containing dissimilar crack, pore media in unsaturation situation, and the seismic wave attenuation of this model of computational prediction and frequency dispersion.

It should be noted that, each embodiment in this instructions all adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar part mutually see.For device class embodiment, due to itself and embodiment of the method basic simlarity, so description is fairly simple, relevant part illustrates see the part of embodiment of the method.

Finally, also it should be noted that, in this article, the such as relational terms of first and second grades and so on is only used for an entity or operation to separate with another entity or operational zone, and not necessarily requires or imply the relation that there is any this reality between these entities or operation or sequentially.And, term " comprises ", " comprising " or its any other variant are intended to contain comprising of nonexcludability, thus make to comprise the process of a series of key element, method, article or equipment and not only comprise those key elements, but also comprise other key elements clearly do not listed, or also comprise by the intrinsic key element of this process, method, article or equipment.When not more restrictions, the key element limited by statement " comprising ... ", and be not precluded within process, method, article or the equipment comprising described key element and also there is other identical element.

For convenience of description, various unit is divided into describe respectively with function when describing above device.Certainly, the function of each unit can be realized in same or multiple software and/or hardware when implementing the application.

As seen through the above description of the embodiments, those skilled in the art can be well understood to the mode that the application can add required general hardware platform by software and realizes.Based on such understanding, the technical scheme of the application can embody with the form of software product the part that prior art contributes in essence in other words, this computer software product can be stored in storage medium, as ROM/RAM, magnetic disc, CD etc., comprising some instructions in order to make a computer equipment (can be personal computer, server, or the network equipment etc.) perform the method described in some part of each embodiment of the application or embodiment.

Above the method and system of a kind of seismic wave attenuation prediction that the application provides are described in detail, apply specific case herein to set forth the principle of the application and embodiment, the explanation of above embodiment is just for helping method and the core concept thereof of understanding the application; Meanwhile, for one of ordinary skill in the art, according to the thought of the application, all will change in specific embodiments and applications, in sum, this description should not be construed as the restriction to the application.

Claims (11)

1. a method for seismic wave attenuation prediction, it is characterized in that, the method comprises:

In conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism;

In conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot;

In conjunction with periodicity stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream;

In conjunction with the boundary condition of feature unit, calculate attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream;

According to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

2. method according to claim 1, is characterized in that, described in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculates saturated fluid situation and only comprises containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion:

Calculate fluid in mixed type crack and squeeze spray and the pore-fluid pressure that causes;

The bulk modulus of saturated rock is calculated according to described pore-fluid pressure;

According to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

3. method according to claim 2, is characterized in that, described in conjunction with Biot elastic wave prorogation theory, calculates saturated fluid situation and flows the wave attenuation in length and breadth of attenuating mechanism containing micro-scale injection stream and macro-scale Biot and frequency dispersion comprises:

According to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculate the Time Migration of Elastic Wave Equation containing hole, mixed type crack;

Decoupling zero is carried out to described Time Migration of Elastic Wave Equation and obtains compressional wave equation and shear wave equation;

According to described compressional wave equation and described shear wave equation, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

4. method according to claim 3, is characterized in that, described combination is stratiform patchy saturation periodically, calculates unsaturation fluid situations and only comprises containing the seismic wave attenuation of micro-scale injection stream and meso-scale local stream and frequency dispersion:

According to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtain the ground roll modulus that frequently flattens;

Unsaturation fluid situations is calculated only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream and medium measure local stream according to the described frequency ground roll modulus that flattens.

5. method according to claim 4, is characterized in that, the described boundary condition in conjunction with feature unit, calculates unsaturation fluid situations and comprises containing the attenuation of P-wave of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream and frequency dispersion:

According to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculate upper and lower solid displacement;

Body according to described solid displacement calculation feature unit becomes;

The definition of bulk modulus is utilized to calculate the ground roll modulus that frequently flattens;

Flattening according to described frequency, ground roll modulus calculating unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot flows and the quantitative expression of the seismic wave attenuation of medium measure local stream attenuating mechanism;

Utilize the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, calculate unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.

6. method according to claim 5, is characterized in that, described Biot elastic wave prorogation theory comprises:

The mass conservation condition of elastic constitutive model equation, nonlinear New-tonian law and pipeline stream.

7. a system for seismic wave attenuation prediction, it is characterized in that, this system comprises:

First computing unit: in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing seismic wave attenuation and the frequency dispersion of micro-scale injection stream attenuating mechanism;

Second computing unit: in conjunction with Biot elastic wave prorogation theory, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot;

3rd computing unit: for combining periodically stratiform patchy saturation, calculate seismic wave attenuation and frequency dispersion that unsaturation fluid situations only contains micro-scale injection stream and meso-scale local stream;

4th computing unit: for the boundary condition in conjunction with feature unit, calculates attenuation of P-wave and frequency dispersion that unsaturation fluid situations contains micro-scale injection stream, macro-scale Biot stream and meso-scale local stream;

Predicting unit: for according to described calculating each decay and frequency dispersion result carry out seismic wave attenuation prediction.

8. system according to claim 7, is characterized in that, described first computing unit comprises:

5th computing unit: squeeze spray and the pore-fluid pressure that causes for calculating fluid in mixed type crack;

6th computing unit: for calculating the bulk modulus of saturated rock according to described pore-fluid pressure;

7th computing unit: for according to described pore-fluid pressure and described bulk modulus, in conjunction with the mechanical function mechanism under draining and non-drainage condition, calculate saturated fluid situation only containing the seismic wave attenuation under micro-scale injection stream attenuating mechanism condition and frequency dispersion.

9. system according to claim 8, is characterized in that, described second computing unit comprises:

8th computing unit: for according to described pore-fluid pressure, in conjunction with Biot elastic wave prorogation theory, calculates the Time Migration of Elastic Wave Equation containing hole, mixed type crack;

First solves unit: obtain compressional wave equation and shear wave equation for carrying out decoupling zero to described Time Migration of Elastic Wave Equation;

9th computing unit: for according to described compressional wave equation and described shear wave equation, calculate saturated fluid situation flows attenuating mechanism wave attenuation in length and breadth and frequency dispersion containing micro-scale injection stream and macro-scale Biot.

10. system according to claim 9, is characterized in that, described 3rd computing unit comprises:

Second solves unit: for according to described pore-fluid pressure, in conjunction with periodicity stratiform patchy saturation, obtain the ground roll modulus that frequently flattens;

Tenth computing unit: the seismic wave attenuation and the frequency dispersion that only contain micro-scale injection stream and medium measure local stream for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency.

11. systems according to claim 10, is characterized in that, described 4th computing unit comprises:

11 computing unit: for according to described compressional wave equation, in conjunction with the boundary condition of feature unit, calculates upper and lower solid displacement;

12 computing unit: become for the body according to described solid displacement calculation feature unit;

13 computing unit: calculate the ground roll modulus that frequently flattens for utilizing the definition of bulk modulus;

14 computing unit: the quantitative expression containing the seismic wave attenuation of micro-scale injection stream, macro-scale Biot stream and medium measure local stream attenuating mechanism for the ground roll modulus calculating unsaturation fluid situations that flattens according to described frequency;

3rd solves unit: for utilizing the method for Concerning With Fast-slow Waves decoupling zero to solve described quantitative expression, obtains unsaturated flow concrete conditions in the establishment of a specific crime only containing attenuation of P-wave and the frequency dispersion of micro-scale injection stream, macro-scale Biot stream and meso-scale local stream.