CN111399031B - A method of collecting and processing mountain seismic data - Google Patents

Abstract

The invention discloses a method for collecting and processing mountain seismic data, which relates to the field of oil and gas exploration. After processing the data, the seismic profile and depth velocity model are obtained, and the seismic data acquisition of the piedmont zone is carried out by designing a virtual VSP acquisition system, and the correction of the relevant shot points and detection points is carried out; seismic data processing using non-zero offset VSP method, the relevant seismic data is processed; and then the coordinates of the CDP point in the pseudo-VSP seismic profile data are converted into coordinates, so as to be adjusted to the seismic profile displayed in the measured coordinate system, and the seismic data collected according to the present invention and related The processing results can be used for structural interpretation of complex structural belts, reservoir prediction, fracture prediction, and provision of relevant depth velocity models.

Description

A method of collecting and processing mountain seismic data

technical field

The invention relates to the field of oil and gas exploration, in particular to a method for collecting and processing mountain seismic data.

Background technique

In the field of geophysical exploration, after acquiring seismic data through conventional seismic acquisition methods, it is necessary to process, interpret and invert the seismic data, and use the obtained results to demonstrate exploration well locations. Therefore, the seismic data obtained by seismic acquisition and related processing techniques have a great influence on the subsequent seismic interpretation work, which determines the success or failure of the subsequent related work. In the processing of mountain seismic data, it is very important to obtain the depth and velocity of the formation, which is related to the success or failure of the pre-stack depth migration imaging.

A large number of exploration practices have shown that conventional seismic reflection imaging is not ideal in high and steep structural areas. For example, in some exploration areas in the basin margin belt of northeastern Sichuan, the obtained seismic data cannot be accurately imaged due to poor excitation and reception conditions. In addition, multiple and multiple imaging processes are performed on the seismic data. Regardless of techniques such as pre-stack depth migration or post-stack migration, the relevant processing results cannot be used for interpretation work. As a result, the oil and gas exploration work in this exploration area has come to a standstill. In today's oil and gas exploration, the piedmont belt has attracted the attention of relevant oil and gas exploration companies, and a batch of high-yield oil and gas streams have been drilled in the piedmont belt. Therefore, the piedmont is now a key research area in oil and gas exploration.

In general, in addition to the high cost of acquisition, the seismic exploration of the piedmont zone is restricted by the problem of seismic data imaging. Mainly due to the complex structure of the piedmont zone and the phenomenon of stratum inversion. Such geological conditions lead to inaccurate calculation of the layer velocity of the formation, thus affecting the processing and imaging effects of related conventional seismic data, such as conventional pre-stack depth migration processing. Therefore, it is also crucial to obtain a relatively accurate depth velocity model in mountainous areas. Some invention patents, such as "A method of shot point migration based on terrain factor", propose to calculate the slope value of the terrain factor of the working area according to the digital elevation model of the working area, and obtain the digital model file of the slope of the working area. Interpolate to get the slope value of each shot point. According to the slope value of each shot point and the set slope limit, determine the shot point that needs to be offset, and the longitudinal and lateral offset limit values of the shot point that needs to be offset. Within the range, select the position that satisfies the set slope limit, and offset the shot point that needs to be offset; the invention patent such as "Optimization Design Method of 3D Seismic Observation System Based on Geological and Geophysical Model" proposes to establish a first The three-dimensional wave equation numerical simulation of the virtual spectrum method and the three-dimensional seismic physical model simulation are combined forward modeling to complete the data acquisition work. Based on the reflection points, pre-stack depth migration is performed on the collected data to obtain several imaging results of seismic processing. Seismic imaging results. Judging from the related achievements of mountain seismic data acquisition and processing in recent years, there are mainly the following problems:

(1) The acquisition system established on the conventional plain is not suitable for the acquisition of mountain seismic data, and it is urgent to establish a system suitable for the acquisition of mountain seismic data.

(2) Conventional seismic data processing technology is not suitable for mountain seismic data processing. It is also necessary to establish a set of technical methods different from conventional seismic data processing to make it suitable for mountain seismic data processing.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a method for collecting and processing mountain seismic data, so as to solve the problems of establishing a depth velocity model in a mountain area and inaccurate seismic data imaging in conventional seismic data processing, and is economically feasible and technically feasible. Features of strong operability.

A method for collecting and processing mountain seismic data provided by the present invention includes:

(1) Design a virtual VSP observation system according to the piedmont and its topography, collect seismic data, and obtain relevant seismic data;

(2) According to the virtual VSP observation system and related processing technology, the acquired seismic data are processed to obtain the seismic profile and depth velocity model.

The piedmont zone refers to an area where the relevant surface landforms undergo relatively drastic changes. The front of the piedmont zone is generally a flat area with little surface fluctuation, and the mountains in it are mainly hills with small height differences. On the other hand, the front of the mountain and the mountain have a large height difference with the plain in front of it. The rocks in the tall mountain area are relatively exposed, the weathering layer is less covered, the plants are generally not tall, and the top of the mountain is relatively flat. On the other hand, the plain or hilly area in front of the mountain has thicker regolith, relatively rich vegetation, tall and relatively flat terrain. The edge of the mountain is generally high and steep. From the relevant satellite images, we can understand the difference and dividing line between the piedmont and the plain.

Further, the step (1) specifically includes,

(1-1) Design seismic lines according to the geological conditions and topographic conditions of the piedmont zone;

(1-2) Perform forward analysis on the rays of the target layer to determine the parameters of the field observation system;

(1-3) Implement seismic data acquisition through a seismic data acquisition system.

Further, the step (1-1) specifically includes,

Set up the detection point (reception) in the low part of the plain area of the piedmont and the slope part of the mountain;

Set a shot (excitation) on top of the hill.

Or exchange the excitation and reception positions of the two.

The main feature of the virtual VSP observation system is that it is not received in the well, but the relevant excitation points are set on the top surface of the mountain in the piedmont, and the receiving points are set on the plains and slopes below the mountain. In this way, the positional relationship of shot points and detection points designed to form an inverted "L" type non-zero offset VSP observation system relative to the relationship between well and surface.

Further, the parameters of the field observation system include the position, moving direction and distance of the shot point and the detection point, and the position of the shot point and the detection point and the relevant parameters such as the moving direction and distance are designed according to the actual VSP observation system;

The distance between the shot point and the receiver point is equidistant or unequal;

It is also possible to make the moving direction of the shot point and the receiver point consistent or non-uniform, or set the receiver point to remain stationary, and move the excitation and reception mode of the shot point. In this way, a two-dimensional seismic data acquisition system can be formed. This seismic data acquisition system is similar to the conventional two-dimensional data acquisition system. After the seismic data acquisition is carried out on the designed seismic data acquisition system, the relevant seismic data volume is obtained.

Further, the step (2) specifically includes,

(2-1) Correct the positions of shot points and detection points in the seismic data collected in the field, and correct the measured coordinates and elevations to the virtual VSP observation system, so as to form relevant virtual well depth receiving points and surface excitation point;

(2-2) Add the corrections of shot points and receiver points to the seismic tracehead data, and process them to obtain the initial VSP seismic profile;

(2-3) The CDP coordinate transformation is performed on the initial VSP seismic profile to obtain a pseudo-VSP seismic profile that matches the position of the measured seismic profile.

Further, the step (2-1) specifically includes,

Determine the measured virtual wellhead point (x _o , yo , _{h o )} and virtual bottom hole point (x _o , yo , _hi )

Correct the shot point and detection point respectively to the set virtual surface line and virtual well trajectory;

The virtual well trajectory is a straight line connecting the virtual wellhead point and the virtual bottom hole point and is perpendicular to the reference plane;

The virtual surface line is a straight line drawn from the wellhead point that is perpendicular to the virtual well trajectory and is parallel to the reference plane;

The virtual bottom hole is a position with a relatively small elevation, and is relatively close to the position of the piedmont, and does not affect the related seismic excitation, signal-to-noise ratio and resolution of reception.

Further, the step (2-2) specifically includes,

According to the measured coordinates and elevation data of the shot point and the receiver point, respectively use the replacement velocity and distance data to calculate the vertical distance from the virtual surface line or the virtual well trajectory to obtain the static correction amount of the corresponding shot point and the receiver point;

Correct the seismic data of the corresponding shot point and receiver point by using the static correction amount, and correct the related shot point and receiver point to the virtual surface line and virtual well trajectory respectively;

Combined with the surface geological conditions of the mountainous area, the conventional non-zero offset VSP processing flow is used to process the seismic data to obtain the initial VSP seismic profile.

Further, the step (2-3) specifically includes,

Establish the mathematical relationship between the virtual coordinate system of the virtual VSP observation system and the measured coordinate system;

Establish the two-dimensional coordinate relationship between the shot point and the receiver point;

Through the conversion formula between the virtual coordinate system and the measured coordinate system, the CDP point coordinates of the virtual VSP observation system are converted to the CDP point coordinates in the measured coordinate system, and the buried depth and velocity of the relevant horizons are obtained, and the seismic profile is displayed. .

Further, the virtual coordinate system specifically takes the virtual surface line as the X-axis and the virtual well trajectory as the H-axis to establish a virtual coordinate system with the virtual wellhead point as the origin.

By adopting the above technical scheme, the beneficial effects of the present invention are: by designing a virtual VSP acquisition system, the seismic data acquisition of the piedmont zone is carried out, and the correction of the relevant shot points and detection points is carried out; The data processing method is to process the relevant seismic data; then, the coordinates of the CDP points in the pseudo-VSP seismic profile data are converted into coordinates to adjust to the seismic profile displayed in the measured coordinate system. The seismic data and related processing results collected according to the present invention can be used for structural interpretation of complex structural belts, reservoir prediction, fracture prediction and provision of relevant depth velocity models, etc. The information contained is more and accurate, economically feasible, and technically reliable.

Description of drawings

The invention will be described by way of example and with reference to the accompanying drawings, in which:

1 is a schematic flowchart of a method for designing seismic acquisition parameters according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of relevant seismic acquisition parameters, virtual well trajectory and surface line according to an embodiment of the present invention.

Detailed ways

All features disclosed in this specification, or all disclosed steps in a method or process, may be combined in any way except mutually exclusive features and/or steps.

The present invention will be further described below with reference to the accompanying drawings.

The execution subject of this embodiment is seismic acquisition parameter design, and an observation system and seismic data processing method for the designed seismic acquisition parameters are established. Specifically, a pseudo-VSP system is designed for the acquisition and processing of mountain seismic data, and the obtained seismic data is subjected to non-zero bias VSP data processing after relevant correction, so as to provide relatively accurate depth and velocity models and seismic profiles. It has the characteristics of relative economy and high feasibility, and it is worth popularizing in the seismic exploration of the piedmont zone in the relevant exploration area.

1 is a schematic diagram of the design and processing flow of seismic acquisition parameters for a certain piedmont zone according to an embodiment of the present invention. As shown in FIG. 1 , a method for acquiring mountain seismic data provided by the present invention includes:

① Design the relevant virtual VSP observation system according to the piedmont and its topography, and collect the relevant seismic data and obtain the relevant seismic data;

②According to the virtual VSP observation system and related processing technology, implement seismic data processing and coordinate transformation on the collected seismic data to obtain the relevant seismic profile and depth velocity model;

Design a virtual VSP observation system according to the piedmont and its topography, and collect and process the relevant seismic data to obtain the relevant seismic data, including the following steps:

In step 1, a related virtual VSP observation system is designed according to the piedmont belt and its topography, and the related seismic data is collected and obtained. The main operation is to establish a virtual VSP observation system suitable for the piedmont. The acquisition of the system is mainly based on the design of the relevant seismic lines according to the geological conditions and topographic conditions of the piedmont area. The survey line is mainly in the form of conventional two-dimensional seismic exploration. The relevant detection points are designed in the low part of the plain area of the piedmont and the slope of the mountain to form a part of the two-dimensional survey line. The detection point interval is in the vertical direction. Projection (on the virtual well trajectory) can be set in equidistant or non-equidistant settings; set shot points on the top of the mountain, and the projection of shot points on the datum plane can be set in equidistant or non-equidistant settings. And use the relevant seismic acquisition forward modeling software to implement the ray forward modeling analysis for the target layer, so as to determine the corresponding field observation system parameters.

Among them, the piedmont zone refers to the area where the relevant surface landforms have undergone relatively drastic changes. The front of the piedmont zone is generally a gentle area with little fluctuation of the surface, and the mountains are mainly hills with small height differences. On the other hand, the front of the mountain and the mountain have a large height difference with the plain in front of it. The rocks in the tall mountain area are relatively exposed, the weathering layer is less covered, the plants are generally not tall, and the top of the mountain is relatively flat. On the other hand, the plain or hilly area in front of the mountain has thicker regolith, relatively rich vegetation, tall and relatively flat terrain. The edge of the mountain is generally high and steep. From the relevant satellite images, we can understand the difference and dividing line between the piedmont and the plain.

Among them, the main feature of the virtual VSP observation system is that it is not received in the well, but the relevant receiving geophones are set in the slope part of the piedmont belt and the low part of the plain, and the excitation point is set on the mountain top area. In this way, the designed positional relationship between the shot point and the receiver point forms an inverted "L" type non-zero offset VSP observation system relative to the relationship between the well and the surface. According to the actual non-zero VSP observation system and forward modeling results, a The position of the shot point and the detection point and the related moving direction, distance and other parameters. The distance between the shot point and the detection point of the present invention can be equidistant or unequal distance, the moving direction of the shot point and the detection point can be consistent or non-uniform, or it can be set so that the detection point does not move, and the excitation of the shot point moving In this way, a two-dimensional seismic data acquisition system can be formed. This seismic data acquisition system is similar to the conventional two-dimensional data acquisition system. After the seismic data acquisition is carried out on the designed seismic data acquisition system, the relevant seismic data volume is obtained.

In step 2, according to the virtual VSP observation system and related processing technology, seismic data processing and coordinate transformation are performed on the acquired seismic data to obtain the relevant seismic profile and depth velocity model, including the following steps:

① Correct the position of shot point and detection point to make it correct to the relevant inverted "L" type non-zero offset VSP observation system. The specific operation is to connect the virtual wellhead point (x _o , y _o , h _o ), the virtual bottom hole point ( _xi , _yi , _hi ), and the virtual surface line data, and connect the virtual wellhead point and the virtual bottom hole point. It is set as a virtual well trajectory, and a straight line perpendicular to the virtual well trajectory is drawn from the wellhead point as a virtual surface line. Correct the shot point and detection point to the set virtual surface line and virtual well trajectory respectively. The virtual surface line is a straight line parallel to the reference plane (plane), that is, the elevation of the virtual wellhead (h _o ) is the same. is the location of the designed detection point. The virtual well trajectory is also a straight line, which is generated by intersecting a vertical line from the virtual wellhead to the reference plane and a certain point on the surface. In principle, the surface point is a position with relatively small elevation and is relatively close to the position of the piedmont, which does not affect the related seismic excitation, received signal-to-noise ratio and resolution. In the processing of the acquired seismic data, the three parameters of the relevant wellhead points (x _o , yo , _{ho )} can also be tested, and the appropriate virtual wellhead points (x _o , yo , _{ho )} are preferably entered into the relevant wellhead points. in the processing flow. In actual operation, according to the measured coordinates (x _j , y _j ) and elevation data (h _j ) of the shot point and the detection point, the two are respectively used to replace the speed and the related distance data—with the related virtual surface line or virtual well trajectory. The vertical distance is calculated to obtain the static correction amount of the relevant shot point and detection point. In the technology of the present invention, the set measured three-dimensional coordinate system is consistent with the coordinate system used in actual seismic exploration, that is, the x and y coordinate axes on the plane plus an h axis perpendicular to the plane, the depth h Defined as positive values above sea level and negative values below sea level.

(2) Use the correction amounts of shot points and detection points corrected for the virtual VSP well system to be added to the seismic trace head data, and use the relevant non-zero offset VSP processing flow and software and hardware to process the seismic data to obtain the seismic data processing profile. The virtual coordinate data on the CDP of the pseudo-VSP seismic section is calculated by the relevant transformation, so as to obtain the pseudo-VSP seismic section that is consistent with the measured coordinate system. Specifically, the relevant operation steps are to use the relevant static correction amount to respectively correct the seismic data of the shot point and the detection point, and respectively correct the relevant shot point and the detection point to the virtual surface line and the virtual well trajectory. Then, combined with the surface geological conditions of the mountainous area, the conventional non-zero offset VSP processing flow is used to process the seismic data, so as to obtain a VSP seismic profile.

Among them, the seismic data of shot points and receiver points are respectively corrected by the relevant static correction amount, and the relevant shot points and receiver points are respectively corrected to the virtual surface line and the virtual well trajectory, and the virtual coordinate system is established and the virtual coordinate system is established. Mathematical relationship for conversion between the system and the measured coordinate system. In actual operation, a virtual coordinate system with the virtual wellhead as the origin is established with the virtual surface line as the X axis and the virtual well trajectory as the H axis, and the mathematical conversion relationship between the virtual coordinate system and the measured coordinate system is obtained. By establishing a virtual coordinate system, the two-dimensional coordinate relationship between the shot point and the receiver point is established, so that a two-dimensional seismic section can be generated. In general, after setting the coordinate axis of the virtual surface line as the X axis, this axis is also the coordinate axis where the CDP point in the pseudo VSP seismic section is located. Through the conversion relationship formula between the virtual coordinate system and the measured coordinate system, the CDP point coordinates of the pseudo VSP seismic profile can be converted to the CDP point coordinates in the measured coordinate system, and the buried depth and velocity of the relevant horizon can be obtained, and the seismic profile can be obtained. display etc.

In this step, the seismic data obtained by the technology of the present invention is processed by using the conventional non-zero offset VSP processing flow mainly in combination with the surface geological conditions of the mountainous area, so as to obtain a VSP seismic section passing through a virtual well, and the false The CDP point coordinates of the VSP seismic profile are converted to obtain the coordinate values in the measured coordinate system, which can be displayed according to the relevant CDP points in the measured coordinate system. In addition, the strata, lithology, velocity and other information on the relevant virtual well trajectory can be obtained from the surface geology of the mountainous area, so as to provide parameters and calibration for the relevant VSP data processing. The coordinates of the CDP points of the processed pseudo-VSP seismic profile are transformed, so that the related data of the seismic profile after the coordinate transformation can be displayed in the same way as the measured conventional seismic profile, so as to complete the acquisition and processing of the related mountain seismic data, and get the real mountain The geological conditions of the underground forezone serve related oil and gas exploration. In addition, the horizon interpretation data and horizon velocity data of the virtual VSP seismic data obtained by the technology of the present invention can provide an accurate velocity depth model for the related prestack depth migration processing.

Among them, the non-zero offset VSP processing flow mainly includes preprocessing, same-depth stacking, first-arrival picking, spectrum analysis and bandpass filtering, source wavelet shaping, static time shifting and alignment, wave field separation, deconvolution and VSPCDP stacking imaging, offset imaging, etc. At this stage, the non-zero bias VSP processing technology is very mature, and there are relatively many technical methods.

In addition, according to the example of the present invention, the relevant technical personnel can expand the related mountain acquisition methods, such as the excitation method on the top of the mountain body and the three-dimensional reception on the plane, etc., and design a related seismic processing system to implement seismic data processing and processing. Coordinate transformation and seismic data processing are performed on relevant data volumes.

The above steps are described below with reference to specific embodiments.

In this example, the acquisition and processing of seismic data for the piedmont zone is carried out for the detection of marine shale layers in a high and steep part of a three-dimensional work area, which is mainly performed according to the technical process of the present invention (Fig. 1). Due to the influence of various interference and processing methods, the 2D seismic data in this exploration area has unclear imaging of the target layer, which cannot meet the requirements for interpretation of relevant seismic data. Therefore, in order to illustrate the acquisition and processing effect of the technology of the present invention, the acquisition system of the present invention is arranged on the original two-dimensional seismic survey line. In this way, the relative seismic data are compared to judge the pros and cons of the seismic profiles obtained by the conventional and the invented technology.

In step 1, during the actual seismic data acquisition process for shale gas in a certain exploration area, a related two-dimensional seismic observation system is established to implement seismic data acquisition, thereby forming an inverted "L"-shaped virtual VSP acquisition system (Fig. 2) . The shot points (excitation points) were arranged on the high parts of the mountainous area, and the detection points were set up on the slopes and plains of the mountainous area. The interval of the detection points was 4m to 10m. The total length of the detection point line was about 4.1km, and the vertical direction was 2421m. The layout of the detection points is along the piedmont flat and the gentle slope to the bottom. The shot point interval is large or small. The overall shot distance varies from 10 to 40m. There are nearly 1292 shot points in the relevant range. The design can be offset within a certain range to the left and right of the virtual surface line, in line with relevant acquisition specifications. According to the relevant seismic acquisition design, complete the seismic data acquisition on the line, and obtain the relevant seismic data.

In step 2, relevant seismic data processing is performed on the acquired seismic data to obtain relevant seismic data for interpretation of the seismic data. According to the seismic data collected in the field, static correction of shot points and detection points is carried out for the virtual surface line and virtual well trajectory, and the relevant correction amount is obtained. And for the non-zero offset VSP seismic data processing, the related technical process is established. Using relevant processing software and hardware equipment, implement seismic data processing to obtain pseudo-VSP seismic profile data. And the CDP coordinate transformation is carried out on the seismic profile, and a pseudo-VSP seismic profile is obtained which is consistent with the position of the measured seismic profile.

The actual operation shows that the field seismic data acquisition and processing work for the piedmont zone, compared with the original two-dimensional seismic profile, has the characteristics of clear reflection of the target layer and accurate structural imaging, which is superior to the results of conventional two-dimensional seismic acquisition. . In addition, it is in good agreement with the calibration of the well-seismic synthetic record of a shale gas well laid on the survey line, which achieves the geological purpose.

The foregoing description shows and describes a preferred embodiment of the present invention, but as previously mentioned, it should be understood that the present invention is not limited to the form disclosed herein, and should not be construed as an exclusion of other embodiments, but may be used in various and other combinations, modifications and environments, and can be modified within the scope of the inventive concepts described herein, from the above teachings or from skill or knowledge in the relevant art. However, modifications and changes made by those skilled in the art do not depart from the spirit and scope of the present invention, and should all fall within the protection scope of the appended claims of the present invention.

Claims (7)

1. A method for collecting and processing mountain land seismic data is characterized by comprising the following steps: comprises that

(1) Designing a virtual VSP observation system according to the mountain front zone and the terrain thereof, and acquiring seismic data; the step (1) specifically comprises the following steps,

(1-1) designing a seismic survey line according to the geological condition and the topographic condition of the mountain front zone;

the step (1-1) specifically comprises the steps of arranging wave detection points at the low part of a plain area of a mountain front zone and the slope part of a mountain body; setting a shot point at the top of the mountain; or interchanging the two;

(1-2) performing forward analysis on rays of a target layer to determine parameters of a field observation system;

(1-3) performing seismic data acquisition by a seismic data acquisition system;

(2) and processing the acquired seismic data to obtain a seismic section and a depth velocity model.

2. The method for collecting and processing mountain seismic data as claimed in claim 1, wherein: the field observation system parameters comprise positions, moving directions and distances of a shot point and a wave detection point;

the distance between the shot point and the wave detection point is equal or unequal;

the moving directions of the shot point and the wave detection point are consistent or inconsistent or the wave detection point is set to be fixed, and the shot point is moved.

3. The method for collecting and processing mountain seismic data as claimed in claim 1, wherein: the step (2) specifically comprises the following steps,

(2-1) correcting the positions of shot points and wave detection points to the virtual VSP observation system;

(2-2) adding the correction values of the shot point and the demodulator probe into the seismic channel head data, and processing to obtain an initial VSP seismic section;

and (2-3) carrying out CDP coordinate transformation processing on the initial VSP seismic section to obtain a pseudo VSP seismic section matched with the position of the actually measured seismic section.

4. The method for collecting and processing mountain seismic data as claimed in claim 3, wherein: the step (2-1) specifically comprises the steps of,

respectively correcting the shot point and the wave detection point to a set virtual earth surface line and a set virtual well track;

the virtual well track is a straight line connecting the virtual wellhead point and the virtual well bottom point and is vertical to the reference surface;

the virtual earth surface line is a straight line which is led out from a wellhead point and forms a perpendicular line with the virtual well track and is parallel to the reference surface;

the virtual well bottom point is a position with a relatively small elevation and is relatively close to the position of the mountain front zone, and the signal-to-noise ratio and the resolution of the related earthquake excitation and receiving are not influenced.

5. The method for collecting and processing mountain seismic data as claimed in claim 3, wherein: the step (2-2) specifically comprises the steps of,

calculating the vertical distance between the shot point and the demodulator probe and the virtual earth surface line or the virtual well track by respectively using the replacement speed and the distance data according to the actually measured coordinates and elevation data of the shot point and the demodulator probe so as to obtain the static correction value of the corresponding shot point and demodulator probe;

correcting the seismic data of the corresponding shot points and the corresponding demodulator probes by using the static correction values, and respectively correcting the relevant shot points and demodulator probes to the virtual earth surface line and the virtual well track;

and (3) combining the surface geological condition of the mountain area, and performing seismic data processing by using a conventional non-zero-bias VSP processing flow to obtain an initial VSP seismic profile.

6. The method for collecting and processing mountain seismic data as claimed in claim 3, wherein: the step (2-3) specifically comprises the steps of,

establishing a mathematical relation formula for conversion between a virtual coordinate system and an actually measured coordinate system of a virtual VSP observation system;

establishing a two-dimensional coordinate relationship between a shot point and a wave detection point;

and converting the CDP point coordinate of the virtual VSP observation system into the CDP point coordinate in the actual measurement coordinate system through a conversion relation formula between the virtual coordinate system and the actual measurement coordinate system, and performing buried depth and speed calculation and seismic section display of the related layer.

7. The method for collecting and processing mountain seismic data as claimed in claim 6, wherein: the virtual coordinate system specifically uses a virtual earth surface line as an X axis and a virtual well track as an H axis to establish a virtual coordinate system using a virtual well head point as an origin.

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