CN103091710A - Reverse time migration imaging method and device - Google Patents

Abstract

The invention relates to a reverse time migration imaging method and a device, wherein the method comprises the following steps: acquiring seismic source wave field information and wave field information of a wave detection point; according to the acquired seismic source wave field information and the acquired wave field information of the wave detection point, the seismic source wave field is separated into a seismic source uplink wave field and a seismic source downlink wave field, and the wave detection point wave field is separated into a wave detection point uplink wave field and a wave detection point downlink wave field; and carrying out reverse time migration imaging processing on the separated seismic source wave field and the separated wave field of the wave detection point to obtain a reverse time migration imaging section. The reverse time migration imaging method and the reverse time migration imaging device eliminate low-frequency noise generated in the reverse time migration process, have high amplitude preservation, keep good parallel characteristics of internal wave field calculation, are very suitable for being carried out on a Graphics Processing Unit (GPU)/Central Processing Unit (CPU) heterogeneous platform, and greatly improve the calculation efficiency of reverse time migration.

Description

A kind of reverse-time migration formation method and device

Technical field

The invention relates to geophysical survey seismic data processing technology field, especially about oil and gas exploration seismic data processing technology field, is about a kind of reverse-time migration formation method and device specifically.

Background technology

Along with the development of oil-gas exploration technology, the target of oil-gas exploration turns to gradually architectonic under complex near surface conditions and intricately " two complexity " zone, and traditional formation method can't satisfy the imaging in " two complexity " zone.The depth migration imaging method that present domestic heavy industrialization is used mainly is based on Kirchhoff integral method and the beam class offset method of ray theory, but these class methods are approximate solutions of wave equation, they can not fine imaging for high steep dip, and complex structure is accompanied by strong lateral speed change usually, therefore result has multipath, thereby can limit the counting yield based on the ray theory offset method.For solving the problems of the technologies described above, prior art provides a kind of wave equation migration algorithm based on the one way ripple, utilize the paraxial approximation theory of wave equation to realize the extrapolation of wave field, can well imaging under specific angle, but when the stratum approached even over 90 degree, this method can lose efficacy equally.

For solving the problems of the technologies described above, prior art proposes a kind of reverse-time migration method, the reverse-time migration method is just proposed in nineteen eighty-two SEG meeting by people such as Whitemore N D. the earliest, but be limited by its huge calculated amount and fancy price, this method never has large-scale application in actual production, and in recent years, along with super large computer cluster and GPU(Graphic Processing Unit, graphic process unit) development of technology, the reverse-time migration technology is gradually by large-scale application.The pre-Stack Reverse method can be divided into for three steps substantially: 1, carry out the forward extrapolation of shot point wave field in time domain; 2, carry out geophone station wave field back-extrapolate in time domain; 3, the position that utilizes effective image-forming condition to occur in the reflection horizon is built into picture.At present, the reverse-time migration wave field extrapolation of heavy industrialization remains and realizes by following Chang Midu ACOUSTIC WAVE EQUATION (1):

$\frac{1}{V^2(x,y,z)}\frac{{\∂}^{2}P}{{\∂t}^2}=\frac{{\∂}^{2}P}{{\∂x}^2}+\frac{{\∂}^{2}P}{{\∂y}^2}+\frac{{\∂}^{2}P}{{\∂z}^2}---\left(1\right)$

Wherein t represents time coordinate, x, and y, z represents volume coordinate, and P represents the wave field pressure field that (x, y, z) locates in the locus, and V represents in length and breadth to variable medium velocity function.In the reverse-time migration imaging process, shot point wave field and geophone station wave field are all realized extrapolation by equation (1), and be embodied as the time usually utilize the zero-lag simple crosscorrelation of shot point and geophone station extrapolation wave field to build image-forming condition, following equation (2):

$I(x,y,z)=\underset{0}{\overset{T_{\max }}{\∫}}s(t,x,y,z)r(t,x,y,z)\mathrm{dt}---\left(2\right)$

In equation (2), s is the source wavefield of forward extrapolation, and r is the geophone station wave field of back-extrapolate, and I is imaging results, T _maxBe the maximum time of wave field extrapolation; Utilize this image-forming condition to carry out reverse-time migration and need to realize three link, at first, source wavefield is carried out the forward continuation, preserve the wave field information of each time step; Then, the geophone station wave field is carried out backward extension, preserve the wave field information of each time step; At last, the source wavefield and the geophone station wave field that read respectively synchronization carry out the imaging computing, add up into imaging space, just can obtain final imaging results.

Yet, the defined image-forming condition of equation (2) can produce the low frequency noise of a large amount of strong amplitudes usually, the skew illusion occurs at some reflecting interfaces places sometimes, particularly above the strong reflection interface, these low frequency noises even can pollute useful signal and the tectonic structure of shallow-layer is thoroughly flooded; In actual application, for effectively eliminating these low frequency noises, generally can adopt following three kinds of main denoising thinkings, that is: denoising in the wave field communication process, filter method denoising after denoising or imaging when using image-forming condition.Yet any in three kinds of denoising schemes all can more or less hurt useful signal, thus guarantor's width of the data of destruction; By analysis and research, the main cause of finding these low frequency noises of generation is that the simple crosscorrelation of source wavefield and geophone station wave field not only can produce amplitude at the reflecting interface place, while is at the non-reflective some place in the whole path that ripple is propagated, also can produce amplitude, if these amplitudes along temporal summation, will be produced the low frequency noise of strong amplitude.In order to eliminate this low frequency noise, must adopt various denoising methods, no matter but which kind of denoising method all can be destroyed the useful signal of data, and destroy guarantor's width of reverse-time migration.

Summary of the invention

For overcoming problems of the prior art, the invention provides a kind of reverse-time migration formation method and device, in actual application, can't produce low frequency noise, have very high guarantor's width.

The invention provides a kind of reverse-time migration formation method, described method comprises: obtain source wavefield information and geophone station wave field information; According to the source wavefield information of obtaining and geophone station wave field information, source wavefield is separated into traveling-wave field under focus upstream wave field and focus, be traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation; Source wavefield and geophone station wave field after separating are carried out the reverse-time migration imaging processing, obtain the reverse-time migration imaging section.

The present invention also provides a kind of reverse-time migration imaging device, and described device comprises: the wave field information acquisition unit is used for obtaining source wavefield information and geophone station wave field information; The wave field separation unit is used for according to source wavefield information and the geophone station wave field information obtained, source wavefield being separated into traveling-wave field under focus upstream wave field and focus, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation; Image-generating unit is used for source wavefield and geophone station wave field after separating are carried out the reverse-time migration imaging processing, obtains the reverse-time migration imaging section.

Reverse-time migration formation method and device that the embodiment of the present invention provides, eliminated the low frequency noise that produces in the reverse-time migration process, has very high guarantor's width, and kept inner wave field to calculate the good Concurrent Feature that has, be highly suitable for GPU/CPU(Central Processing Unit, central processing unit) carry out on heterogeneous platform, improve greatly the counting yield of reverse-time migration.

Description of drawings

Accompanying drawing described herein is used to provide a further understanding of the present invention, consists of the application's a part, does not consist of limitation of the invention.In the accompanying drawings:

Fig. 1 is the process flow diagram of a kind of reverse-time migration formation method of providing of the embodiment of the present invention.

Fig. 2 is the horizontal layer model schematic diagram of the different travel paths of the same source wavefield that provides of the embodiment of the present invention.

Fig. 3 is the process flow diagram of a kind of reverse-time migration formation method of providing of the embodiment of the present invention.

Fig. 4 is a kind of reverse-time migration imaging device module map that the embodiment of the present invention provides.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with embodiment and accompanying drawing, the present invention is described in further details.At this, exemplary embodiment of the present invention and explanation thereof are used for explanation the present invention, but not as a limitation of the invention.

The embodiment of the present invention provides a kind of reverse-time migration formation method and device, and the present invention is described in detail below in conjunction with accompanying drawing.

Embodiment one

Fig. 1 is the process flow diagram of a kind of reverse-time migration formation method of providing of the embodiment of the present invention, and as shown in Figure 1, the reverse-time migration formation method comprises the steps:

S101 obtains source wavefield information and geophone station wave field information.

In embodiments of the present invention, step S101 can comprise following substep:

Obtain single big gun data, and single big gun data are carried out the prestack pre-service;

Forward wave to single big gun data of prestack pre-service output is spreaded to the inverse time extrapolation outside the venue, obtains source wavefield information and the geophone station wave field information of each time step.

Concrete, can load single big gun data of earthquake-capturing; Carry out the prestack pre-service work such as static correction, denoising to loading single big gun data, in order to obtain high s/n ratio, high single big gun data of protecting width; The forward wave that provides relatively accurate velocity field to realize the single big gun data of earthquake on the GPU/CPU heterogeneous platform is spreaded to the inverse time extrapolation outside the venue, obtains source wavefield information and geophone station wave field information and the storage of each time step.

S102 according to the source wavefield information of obtaining and geophone station wave field information, is separated into traveling-wave field under focus upstream wave field and focus with source wavefield, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation.

Fig. 2 is the horizontal layer model schematic diagram of the different travel paths of the same source wavefield that provides of the embodiment of the present invention, and as shown in Figure 2, n represents normal orientation; I represents incident wave; T represents transmitted wave; R represents reflection wave, and along wave trajectory, shot point wave field and geophone station wave field have identical direction usually, and simultaneously, incident field and reflected wave field have opposite direction in the projection of the normal orientation of reflecting interface.The direction of propagation according to source wavefield and geophone station wave field, two wave field separations are become its upstream wave field and lower traveling-wave field separately, the correlativity of carrying out the later focus of wave field separation and geophone station wave field is relevant in the projection of normal direction with its direction of propagation, when they have opposite projecting direction, after two wave field separations, having a meeting at least is zero, only can produce imaging at the reflection spot place, and just can not produce imaging at non-reflective some place.

In embodiments of the present invention, having proposed that a kind of effectively wave field separation becomes the method for its uplink and downlink component with geophone station with source wavefield, is mainly that the uplink and downlink ripple is separated it in the F-K territory.

A bit (x, y, z=z0) locates on the earth's surface, and source wavefield s (t, x, y, z) and geophone station wave field r (t, x, y, z) can realize separating of focus and geophone station wave field uplink and downlink ripple by Fourier transform.At Fourier, upstream wave field can successfully be separated with lower traveling-wave field, and can be expressed as respectively equation:

$S_u(\mathrm{\&omega;},k_z)=\left\{\begin{array}{cc}s(\mathrm{\&omega;},k_z)& {\mathrm{\&omega;k}}_z\&GreaterEqual;0\\ 0& {\mathrm{\&omega;k}}_z<0\end{array}\right.---\left(3\right)$

$S_d(\mathrm{\&omega;},k_z)=\left\{\begin{array}{cc}s(\mathrm{\&omega;},k_z)& {\mathrm{\&omega;k}}_z<0\\ 0& {\mathrm{\&omega;k}}_z\&GreaterEqual;0\end{array}\right.---\left(4\right)$

$R_u(\mathrm{\&omega;},k_z)=\left\{\begin{array}{cc}R(\mathrm{\&omega;},k_z)& {\mathrm{\&omega;k}}_z\&GreaterEqual;0\\ 0& {\mathrm{\&omega;k}}_z<0\end{array}\right.---\left(5\right)$

$R_d(\mathrm{\&omega;},k_z)=\left\{\begin{array}{cc}R(\mathrm{\&omega;},k_z)& {\mathrm{\&omega;k}}_z<0\\ 0& {\mathrm{\&omega;k}}_z\&GreaterEqual;0\end{array}\right.---\left(6\right)$

In formula, S _u, S _dRepresent respectively the Fourier transform of focus uplink and downlink wave field, R _u, R _dRepresent respectively the Fourier transform of geophone station uplink and downlink wave field.

S103 carries out the reverse-time migration imaging processing to source wavefield and geophone station wave field after separating, obtains the reverse-time migration imaging section.

In embodiments of the present invention, source wavefield and geophone station wave field after separating are converted to time domain, just can obtain the time domain image-forming condition based on the reverse-time migration of wave field separation, the expression formula that is converted to time domain is respectively:

$s_u(t,x,y,z)=\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}{S}_u(\mathrm{\&omega;},k_z)e^{i(\mathrm{tw}+{\mathrm{zk}}_z)}{\mathrm{d\&omega;dk}}_z---\left(7\right)$

$s_d(t,x,y,z)=\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}{S}_d(\mathrm{\&omega;},k_z)e^{i(\mathrm{t\&omega;}+{\mathrm{zk}}_z)}{\mathrm{d\&omega;dk}}_z---\left(8\right)$

$r_u(t,x,y,z)=\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}{R}_u(\mathrm{\&omega;},k_z)e^{i(\mathrm{tw}+{\mathrm{zk}}_z)}{\mathrm{d\&omega;dk}}_z---\left(9\right)$

$r_d(t,x,y,z)=\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}\underset{-\&infin;}{\overset{+\&infin;}{\&Integral;}}{R}_d(\mathrm{\&omega;},k_z)e^{i(\mathrm{t\&omega;}+{\mathrm{zk}}_z)}{\mathrm{d\&omega;dk}}_z---\left(10\right)$

In reverse-time migration, focus and geophone station wave field extrapolation utilize omnidistance Acoustic Wave-equation to launch, and it comprises source wavefield and two ingredients of geophone station wave field, can be expressed as respectively expression formula:

s(t,x,y,z)=s _d(t,x,y,z)+s _u(t,x,y,z) (11)

r(t,x,y,z)＝r _d(t,x,y,z)+r _u(t,x,y,z) (12)

In formula, s represents source wavefield, s _dRepresent the lower traveling-wave field of focus, s _uRepresent the upstream wave field of focus, r represents geophone station wave field, r _dRepresent traveling-wave field under geophone station, r _uRepresent the geophone station upstream wave field.Carry it into respectively equation (2) and just can obtain four cross correlation results:

$I(x,y,z)=\underset{0}{\overset{T\max }{\&Integral;}}{s}_d(t,x,y,z)r_u(t,x,y,z)\mathrm{dt}+\underset{0}{\overset{T\max }{\&Integral;}}{s}_u(t,x,y,z)r_d(t,x,y,z)\mathrm{dt}$

$+\underset{0}{\overset{T\max }{\&Integral;}}{s}_d(t,x,y,z)r_d(t,x,y,z)\mathrm{dt}+\underset{0}{\overset{T\max }{\&Integral;}}{s}_u(t,x,y,z)r_u(t,x,y,z)\mathrm{dt}$

$=I_{z1}(x,y,z)+I_{z2}(x,y,z)+I_{z3}(x,y,z)+I_{z4}(x,y,z)---\left(13\right)$

In equation (13), I _z1Under the expression focus, the simple crosscorrelation of traveling-wave field and geophone station upstream wave field (is expressed as I _z1), its essence is the wave equation migration of one way ripple; I _z2The simple crosscorrelation of traveling-wave field under expression focus upstream wave field and geophone station; I _z3The simple crosscorrelation of traveling-wave field under traveling-wave field and geophone station under the expression focus; I _z4The simple crosscorrelation of expression focus upstream wave field and geophone station upstream wave field.According to ray theory, some reflection spots place, incident wave is descending ripple, reflection wave is upward traveling wave; And some reflection spots place, incident wave is upward traveling wave, reflection wave is descending ripple, therefore two reflections is all participated in into, can utilize ray tracing to carry out imaging, that is to say, only needs I _z1And I _z2Two, just can realize the reverse-time migration imaging.The result that remaining two parts produce is low frequency noise, that is to say two wave fields that utilize the direction of propagation identical, no matter be descending ripple I _z3Or upward traveling wave I _z4, they are carried out simple crosscorrelation along whole raypath, its cross correlation results is the low frequency noise of imaging space.At this moment, can obtain the simple crosscorrelation image-forming condition that can effectively eliminate low frequency noise:

I(x,y,z)=I _z1(x,y,z)+I _z2(x,y,z) (14)

The image-forming condition of equation (14) finally is expressed as under time domain:

$I(x,y,z)=\underset{0}{\overset{T_{\max }}{\&Integral;}}[s_d(t,x,y,z)r_u(t,x,y,z)+r_d(t,x,y,z)s_u(t,x,y,z)]\mathrm{dt}---\left(15\right)$

According to equation (15), focus and geophone station wave field after separating are carried out the reverse-time migration imaging, export final reverse-time migration imaging section.

The reverse-time migration formation method that the embodiment of the present invention provides, along wave trajectory, reflection spot and the difference of non-reflective point are come, then only utilize image-forming condition at the reflection spot place, eliminated the low frequency noise that produces in the reverse-time migration process, have very high guarantor's width.

The reverse-time migration formation method that the embodiment of the present invention provides has kept inner wave field to calculate the good Concurrent Feature that has, and non-being everlasting is adapted at carrying out on the GPU/CPU heterogeneous platform, therefore can improve greatly the counting yield of reverse-time migration.

Embodiment two

In order to test Stability and veracity of the present invention, the present embodiment is to most typical BP(British Petroleum in geophysics circle, BP) mathematical model tests.Fig. 3 is the process flow diagram of a kind of reverse-time migration formation method of providing of the present embodiment, and as shown in Figure 3, the reverse-time migration formation method comprises the steps:

S301, the earthquake big gun record that the BP forward modeling is obtained is loaded into the work area.

S302 utilizes effective denoising method, and the various noises in seismologic record are removed in substep minute territory, then again is drawn into the big gun territory.

S303 provides to be used for accurately just drilling the BP mathematical model of single shot record as the velocity-depth model of reverse-time migration.

S304, the forward wave of the single big gun data of earthquake of performing step S302 output on the GPU/CPU heterogeneous platform is spreaded to the inverse time extrapolation outside the venue, and the wave field information of storing each time step.

S305, according to wave field separation method provided by the invention, the wave field that step S304 is stored carries out the separation of uplink and downlink ripple.

S306 utilizes reverse-time migration image-forming condition provided by the invention, focus and geophone station wave field after separating is carried out the reverse-time migration imaging, and export final reverse-time migration imaging section.

The reverse-time migration imaging results that the imaging results that the reverse-time migration image-forming condition that application the present invention is mentioned obtains and traditional correlation Condition obtain compares, can learn, utilize the imaging results that image-forming condition that the embodiment of the present invention provides obtains obviously to be better than the imaging results that traditional image-forming condition obtains, particularly the conformation identification ability to top, strong reflection interface is more powerful.

In embodiments of the present invention, in order to test universality of the present invention, particularly for the validity of open-air actual acquisition data, chosen under certain complicated earth surface, intricately the measured data of 150 square kilometres of geologicstructure area and carried out the reverse-time migration test.According to above-mentioned steps, adopt reverse-time migration image-forming condition provided by the present invention, the imaging results that obtains, with itself and the traditional reverse-time migration image-forming condition of employing, the migration result after the denoising that obtains compares.Can see, the image-forming condition that adopts the present invention to mention, more accurate for the epi-tectonic imaging of data, and increased guarantor's width of data.Recognition capability for the steep dip structure also obviously is better than the imaging results that adopts traditional reverse-time migration image-forming condition to obtain.

The reverse-time migration formation method that the embodiment of the present invention provides, compare with traditional reverse-time migration image-forming condition, maximum advantage is that it has overcome the defective that traditional reverse-time migration image-forming condition can produce the low frequency noise of a large amount of strong amplitudes, directly just omitted the low frequency noise item in utilizing the process of image-forming condition, do not lose effective seismic signal, therefore have higher data and protect width; Meanwhile, reverse-time migration image-forming condition provided by the invention has kept inner wave field to calculate the good Concurrent Feature that has, and non-being everlasting is adapted at carrying out on the GPU/CPU heterogeneous platform, therefore can improve greatly the counting yield of reverse-time migration.

Embodiment three

Fig. 4 is a kind of reverse-time migration imaging device module map that the embodiment of the present invention provides, and the reverse-time migration imaging device adopts method as described in embodiment one to generate the reverse-time migration imaging section, and as shown in Figure 4, the reverse-time migration imaging device comprises:

Wave field information acquisition unit 401 is used for obtaining source wavefield information and geophone station wave field information.

In embodiments of the present invention, wave field information acquisition unit 401 can also comprise:

Pretreatment module is used for obtaining single big gun data, and single big gun data is carried out the prestack pre-service;

The extrapolation process module is spreaded to the inverse time extrapolation outside the venue for the forward wave of single big gun data that the prestack pre-service is exported, and obtains source wavefield information and the geophone station wave field information of each time step.

Wave field separation unit 402 is used for according to source wavefield information and the geophone station wave field information obtained, source wavefield being separated into traveling-wave field under focus upstream wave field and focus, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation.

In embodiments of the present invention, wave field separation unit 402 is separated into traveling-wave field under focus upstream wave field and focus by Fourier transform with source wavefield, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation.

Image-generating unit 403 is used for source wavefield and geophone station wave field after separating are carried out the reverse-time migration imaging processing, obtains the reverse-time migration imaging section.

In embodiments of the present invention, described image-generating unit 403 comprises:

The time domain modular converter, source wavefield and geophone station wave field after being used for separating are converted to time domain, obtain the time domain image-forming condition of reverse-time migration;

The reverse-time migration image-forming module is used for according to the time domain image-forming condition of described reverse-time migration, focus and geophone station wave field after separating being carried out the reverse-time migration imaging, generates the reverse-time migration imaging section.

The reverse-time migration imaging device that the embodiment of the present invention provides, along wave trajectory, reflection spot and the difference of non-reflective point are come, then only utilize image-forming condition at the reflection spot place, eliminated the low frequency noise that produces in the reverse-time migration process, have very high guarantor's width.

The reverse-time migration imaging device that the embodiment of the present invention provides has kept inner wave field to calculate the good Concurrent Feature that has, and non-being everlasting is adapted at carrying out on the GPU/CPU heterogeneous platform, therefore can improve greatly the counting yield of reverse-time migration.

Above-described embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above is only the specific embodiment of the present invention; the protection domain that is not intended to limit the present invention; within the spirit and principles in the present invention all, any modification of making, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims (8)

1. a reverse-time migration formation method, is characterized in that, described method comprises:

Obtain source wavefield information and geophone station wave field information;

According to the source wavefield information of obtaining and geophone station wave field information, source wavefield is separated into traveling-wave field under focus upstream wave field and focus, be traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation;

Source wavefield and geophone station wave field after separating are carried out the reverse-time migration imaging processing, obtain the reverse-time migration imaging section.

2. reverse-time migration formation method according to claim 1, is characterized in that, describedly obtains source wavefield information and geophone station wave field information comprises:

Obtain single big gun data, and single big gun data are carried out the prestack pre-service;

Forward wave to single big gun data of prestack pre-service output is spreaded to the inverse time extrapolation outside the venue, obtains source wavefield information and the geophone station wave field information of each time step.

3. reverse-time migration formation method according to claim 1, is characterized in that, described source wavefield is separated into traveling-wave field under focus upstream wave field and focus, is that under geophone station upstream wave field and geophone station, traveling-wave field comprises with the geophone station wave field separation:

By Fourier transform, source wavefield being separated into traveling-wave field under focus upstream wave field and focus, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation.

4. reverse-time migration formation method according to claim 1, is characterized in that, described source wavefield and geophone station wave field after separating carried out the reverse-time migration imaging processing, obtains the reverse-time migration imaging section and comprise:

Source wavefield and geophone station wave field after separating are converted to time domain, obtain the time domain image-forming condition of reverse-time migration;

According to the time domain image-forming condition of described reverse-time migration, focus and geophone station wave field after separating are carried out the reverse-time migration imaging, generate the reverse-time migration imaging section.

5. a reverse-time migration imaging device, is characterized in that, described device comprises:

The wave field information acquisition unit is used for obtaining source wavefield information and geophone station wave field information;

The wave field separation unit is used for according to source wavefield information and the geophone station wave field information obtained, source wavefield being separated into traveling-wave field under focus upstream wave field and focus, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation;

Image-generating unit is used for source wavefield and geophone station wave field after separating are carried out the reverse-time migration imaging processing, obtains the reverse-time migration imaging section.

6. reverse-time migration imaging device according to claim 5, is characterized in that, described wave field information acquisition unit comprises:

Pretreatment module is used for obtaining single big gun data, and single big gun data is carried out the prestack pre-service;

The extrapolation process module is spreaded to the inverse time extrapolation outside the venue for the forward wave of single big gun data that the prestack pre-service is exported, and obtains source wavefield information and the geophone station wave field information of each time step.

7. reverse-time migration imaging device according to claim 5, it is characterized in that, described wave field separation unit is separated into traveling-wave field under focus upstream wave field and focus by Fourier transform with source wavefield, is traveling-wave field under geophone station upstream wave field and geophone station with the geophone station wave field separation.

8. reverse-time migration imaging device according to claim 5, is characterized in that, described image-generating unit comprises:

The time domain modular converter, source wavefield and geophone station wave field after being used for separating are converted to time domain, obtain the time domain image-forming condition of reverse-time migration;

The reverse-time migration image-forming module is used for according to the time domain image-forming condition of described reverse-time migration, focus and geophone station wave field after separating being carried out the reverse-time migration imaging, generates the reverse-time migration imaging section.

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