Speed model correction method based on well drilling constraint

Abstract

The invention provides a speed model correction method based on well drilling constraint. The speed model correction method based on well drilling constraint comprises the following steps: step 1, constructing an initial speed model; step 2, establishing an interval velocity model through velocity spectrum data; 3, establishing a well calibration time domain model; 4, speed inversion of model constraint is carried out; 5, speed conversion is carried out, and the well calibration average speed is calculated; and step 6, time-depth conversion is carried out through the average velocity after well calibration, and an inversion interval velocity body, a seismic attribute body and horizon data of a depth domain are obtained. According to the velocity model correction method based on the drilling constraint, a three-dimensional time domain velocity model is converted into a three-dimensional depth domain velocity model, and the seismic velocity field and logging are combined, so that time-depth conversion with relatively high transverse and longitudinal accuracy is realized.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield development, and in particular to a velocity model correction method based on drilling constraints. Background Art

[0002] With the continuous advancement of oil and gas exploration and development in my country, 3D seismic technology has become an indispensable key content in every link of the entire process of exploration, development and production. Through 3D seismic data, we can not only study the underground morphology and structure, but also pay more and more attention to the reservoir prediction problem in 3D space. With the rapid development of various seismic attribute analysis technologies and inversion technologies, more and more information can be obtained through 3D seismic data, such as rich information on the distribution of lithology, physical properties and fluids in the underground 3D space. However, since the seismic data obtained from seismic exploration are often in the time domain, even if the 3D seismic data is processed with depth migration, it is difficult to obtain accurate depth information, especially the correspondence with the drilling depth, which cannot meet the accuracy requirements of researchers.

[0003] At present, predecessors have done a lot of research on the time-depth conversion of two-dimensional structural levels, which has become relatively mature. However, these methods do not perform fine time-depth conversion of small layers inside the reservoir in three-dimensional seismic data and correspond to drilling depth and lithology. The seismic data obtained after conversion are often prone to deformation and interlayer phenomena.

[0004] The accuracy and rationality of velocity modeling will determine the accuracy of seismic data after time-to-depth conversion. With the continuous deepening of research, the current velocity modeling methods are mainly divided into velocity modeling methods based on seismic data and velocity modeling methods based on well logging. However, both methods have limitations. The velocity modeling method based on seismic data often has poor accuracy in the vertical direction, while the velocity modeling method based on well logging has low accuracy in the horizontal direction.

[0005] In the Chinese patent application with application number: CN201510080055.2, a nonlinear error correction method for well-constrained two-dimensional seismic variable velocity field is involved. The error correction method includes the following steps: s1, through interpolation method, the stacking velocity of the poor quality section of the two-dimensional work area and the area without seismic data is improved and corrected, and all the stacking velocities on the grid points are polynomially fitted to establish the initial stacking velocity field; s2, the wellhead average velocity is generated; s3, the error function is constructed, that is, the error curves of the stacking velocity near the well and the wellhead average velocity, as well as the stacking velocity of the non-wellside seismic trace are respectively made; s4, the nonlinear change function value obtained in step s3 is used as the correction amount to correct the error of the seismic stacking velocity in the grid point, and a more reasonable and more accurate variable velocity field is established; s5, the time-depth conversion of the interpreted time layer is performed using the corrected variable velocity average velocity model, that is, variable velocity mapping is realized. The invention method is helpful to reduce the error of the variable velocity field, thereby improving the accuracy of variable velocity structure mapping.

[0006] In the Chinese patent application with application number: CN201210462223.0, a modeling method of a layer velocity model of a formation is involved. The method includes: collecting seismic data of a work area; using the seismic data and the drilling data of the work area to generate a layer velocity field; performing reflection tomography velocity iteration processing on the layer velocity field to generate an optimized layer velocity field; extracting layer velocity plane maps of each formation from the optimized layer velocity field; correcting the extracted layer velocity plane maps of each formation using the drilling data; generating a layer velocity field based on the corrected layer velocity plane map; when the correction amount used for correction exceeds a predetermined range, proceeding to the step of performing reflection tomography velocity iteration processing on the generated layer velocity field.

[0007] In the Chinese patent application with application number: CN201610367256.5, a method for constructing a formation velocity model is involved, including: (A) obtaining existing seismic data in a work area; (B) obtaining a pre-stack time migration seismic data body and a pre-stack time migration imaging velocity in the work area; (C) obtaining seismic reflection layer data and fault data in the time domain of each stratum in the work area; (D) obtaining a pre-stack depth migration velocity body in the work area; (E) determining a time-depth curve of a well in the work area based on an acoustic logging curve and a pre-stack time migration seismic data body; (F) obtaining a wellbore seismic pseudo-velocity of a well in the work area; (G) establishing a grid model of the work area; (H) establishing a formation velocity model based on the pre-stack depth migration velocity body, the time-depth curve of the well, the wellbore seismic pseudo-velocity of the well and the grid model of the work area; (I) correcting the formation velocity model using the drilling data to obtain a drilling formation velocity model. According to the method, the accuracy of the formation velocity model can be effectively improved.

[0008] In the Chinese patent application with application number: CN201911325343.4, a method for modeling a well-controlled velocity field is involved, and the steps are as follows: S1, establish a micro-logging shallow surface low-velocity body model, and calibrate the high-speed top interface on the low-velocity body model; S2, use the time-distance curve to perform time difference correction on the low-velocity body model to obtain a shallow area velocity model; S3, establish an initial velocity model for the deep area; S4, collect logging information to establish a well velocity model, and use the well velocity model to correct the initial velocity model; S5, offset the corrected initial velocity model to obtain a well-connected profile; S6, find velocity anomalies based on the well-connected profile, and correct the velocity anomalies; S7, repeat steps S5 and S6 until there are no velocity anomalies, obtain a deep area velocity model, and then obtain the final well-controlled velocity model. This invention method makes full use of micro-logging and logging data, and can effectively improve the accuracy of velocity modeling, reduce modeling errors, and adapt to a variety of terrains during actual use.

[0009] The above existing technologies are greatly different from the present invention and fail to solve the technical problem we want to solve. Therefore, we have invented a new velocity model correction method based on drilling constraints. Summary of the invention

[0010] The object of the present invention is to provide a velocity model correction method based on drilling constraints, which calculates the layer velocity by creating a velocity model function through inverse distance weighting.

[0011] The object of the present invention can be achieved by the following technical measures: a velocity model correction method based on drilling constraints, the velocity model correction method based on drilling constraints comprises:

[0012] Step 1, constructing an initial velocity model;

[0013] Step 2, establishing a layer velocity model through velocity spectrum data;

[0014] Step 3, well calibration time domain model;

[0015] Step 4, perform velocity inversion with model constraints;

[0016] Step 5, perform speed conversion and calculate the average speed of the well calibration;

[0017] Step 6: Perform time-depth conversion using the average velocity to obtain inversion layer velocity, seismic attribute volume, and layer data in the depth domain.

[0018] The purpose of the present invention can also be achieved by the following technical measures:

[0019] In step 1, under the constraints of sequence stratigraphy, an initial velocity model is established by combining velocity spectrum data or fine well-seismic calibration time-depth relationship data.

[0020] Step 1 includes:

[0021] Step 11, interpolating the velocity spectrum into a stacked velocity volume under the seismic three-dimensional grid;

[0022] Step 12: Well seismic calibration to obtain a time-depth relationship, which is one-dimensional data corresponding to time and depth;

[0023] Step 13: adjusting the stratigraphic order of the layers in chronological order and establishing a stratigraphic structural framework;

[0024] Step 14, interpolating the interpreted thinned horizon into a fully covered horizon;

[0025] Step 15: Use the well trajectory and interpreted layer data to participate in the intersection calculation to obtain the time and depth at the layer; and retain it as the constraint point data.

[0026] In step 2, seismic layer velocity modeling based on layer control constraints is carried out. First, the structural framework of the region is established according to the layers interpreted by the seismic interpretation. On the basis of the structural framework, velocity field modeling is carried out considering the lateral and vertical changes in velocity.

[0027] Step 2 includes:

[0028] Step 21, according to the DIX formula, the stacked velocity body obtained by interpolation in the first step is converted into a layer velocity body;

[0029] Step 22, sequentially along the horizon frame, from the shallow horizon to the deep horizon, extracting the horizon velocity along the horizon as the horizon attribute;

[0030] Step 23, extracting the layer velocity trend surface on the layer to obtain the layer velocity change trend along the layer;

[0031] Step 24, smoothing the layer velocity on the layer, so that the layer velocity along the layer is a relatively smooth velocity field, and removing the distorted data in the initial layer velocity;

[0032] Step 25, correcting the smoothed layer velocity according to the layer velocity trend surface;

[0033] Step 26: perform interlayer velocity interpolation according to the depositional modes including syndeposition, top overlap, truncation, and bottom overlap.

[0034] In step 3, the well logging data is normalized using the well logging data or the acoustic logging data obtained while drilling, and the fine layer velocity model established for the target layer is corrected to achieve real-time velocity modeling based on drilling constraints.

[0035] Step 3 includes:

[0036] Step 31, pre-processing the acoustic logging by removing wild values ​​and interpolating missing values;

[0037] Step 32, extracting the compaction trend of the acoustic logging, and extending the top missing section of the acoustic logging according to the compaction trend;

[0038] Step 33, analyzing the value range distribution law of the target layer segment of the logging data, and performing standardization correction on the acoustic logging;

[0039] Step 34, extracting the well bypass of the initial layer velocity model along the well trajectory;

[0040] Step 35, extracting low frequency of the acoustic logging to obtain a low frequency curve of the acoustic logging, and correcting the initial layer velocity of the well bypass channel according to the low frequency curve;

[0041] Step 36, obtaining the correction data of all wells and performing volume correction on the initial interval velocity model;

[0042] Step 37: After well calibration, a relatively accurate time domain interval velocity model can be obtained.

[0043] In step 4, the velocity body after well calibration is used as the initial model, the model is used for constraint, seismic information is added, the weight coefficients of the model and seismic data are extracted, and velocity inversion is performed to obtain the fine layer velocity body, density body and impedance body.

[0044] Step 4 includes:

[0045] Step 41, extracting wavelets of the seismic data based on the post-stack seismic data;

[0046] Step 42: Based on the wavelet, extract inversion parameters of the wellside velocity model trace of the known well;

[0047] Step 43, determining the model modification amount and the seismic data impact weight coefficient to ensure that the resolution of the velocity obtained by inversion meets the requirements;

[0048] Step 44: After the inversion parameters are determined, generalized linear velocity inversion is performed on the corrected layer velocity model.

[0049] In step 5, the layer velocity body and the root mean square velocity body are converted to obtain the average velocity body; the sedimentary mode of the seismic layer is selected through the well time-depth data, and the velocity field space correction is performed on the average velocity body to obtain a better and more accurate average velocity body.

[0050] Step 5 includes:

[0051] Step 51: Perform average velocity conversion based on the high-precision layer velocity;

[0052] Step 52, extracting the time-depth relationship of the known well and extracting the average velocity;

[0053] Step 53: along the well trajectory, compare the average velocity on the well with the average velocity of the initial conversion to obtain a correction value of the average velocity, and interpolate the correction value along the layer to obtain the average velocity correction value on the layer;

[0054] Step 54, according to the layer framework model, the average velocity correction amount on the layer is interpolated in three-dimensional space in sequence to obtain a three-dimensional average velocity correction volume;

[0055] Step 55: Apply the three-dimensional average velocity correction volume to the initial average velocity volume to obtain a high-accuracy average velocity volume.

[0056] In step 6, based on the established high-precision layer velocity field, average velocity field conversion can be performed. By using the average velocity body, the layer velocity body, seismic data body, attribute body, layer, and fault data can be quickly and accurately converted between the time domain and the depth domain.

[0057] Step 6 includes:

[0058] Step 61, under the control of the high-precision and high-accuracy average velocity volume, the velocity volume and the seismic attribute volume in the time domain are sequentially converted to the depth domain;

[0059] Step 62, under the control of the high-precision and high-accuracy average velocity body, sequentially converting the layers in the time domain into the depth domain;

[0060] Step 63: Under the control of the high-precision and high-accuracy average velocity body, the faults in the time domain are sequentially converted to the depth domain.

[0061] The velocity model correction method based on drilling constraints in the present invention is based on velocity model correction technology. Under the constraints of structural and sequence models, the velocity spectrum and other data are combined with drilling acoustic waves, VSP and other data to correct the average velocity field and layer velocity field in the velocity model. The present invention combines seismic data with logging data. On the basis of establishing an initial three-dimensional time domain layer velocity model of the well area, it combines the information of logging while drilling and logging to obtain a more accurate three-dimensional time domain layer velocity model, and obtains an accurate acoustic logging time-depth relationship through fine well-seismic calibration technology, converts the three-dimensional time domain velocity model into a three-dimensional depth domain velocity model, and realizes time-depth conversion with high horizontal and vertical accuracy by combining the seismic velocity field with logging. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A flowchart of a specific embodiment of the velocity model correction method based on drilling constraints of the present invention;

[0063] Figure 2 It is a cross-sectional diagram of a layer-controlled layer velocity model of a certain well area in a specific embodiment of the present invention;

[0064] Figure 3 It is a plane diagram of a layer-controlled layer velocity model of a certain well area in a specific embodiment of the present invention;

[0065] Figure 4 It is an inversion impedance profile diagram of a certain well area in a specific embodiment of the present invention;

[0066] Figure 5 It is an inversion density profile diagram of a certain well area in a specific embodiment of the present invention;

[0067] Figure 6 It is an inversion velocity profile of a certain well area in a specific embodiment of the present invention;

[0068] Figure 7 It is a cross-sectional diagram of the average velocity field of a certain well area in a specific embodiment of the present invention;

[0069] Figure 8 It is a cross-section comparison diagram of a certain well area before and after the average velocity correction in a specific embodiment of the present invention;

[0070] Fig. 9 It is a cross-sectional diagram of the impedance volume in the depth domain of a certain well area in a specific embodiment of the present invention;

[0071] Fig.10 It is a cross-sectional diagram of a density volume in a certain well area in a specific embodiment of the present invention;

[0072] Fig.11 It is a velocity volume profile diagram of a certain well area in a specific embodiment of the present invention;

[0073] Fig.12 This is a plane comparison diagram before and after the time-depth conversion of a certain well area layer in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0074] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0075] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations and / or combinations thereof.

[0076] like Figure 1 As shown, Figure 1 The figure is a flow chart of the velocity model correction method based on drilling constraints of the present invention. The velocity model correction method based on drilling constraints includes:

[0077] (1) Constructing the initial velocity model

[0078] Under the constraints of sequence control, the initial velocity model is established by combining velocity spectrum data or fine well-seismic calibration.

[0079] The specific steps include: 1. The velocity spectrum is text format data, which is a sparse three-dimensional distributed scattered point type data. The velocity spectrum needs to be interpolated into a stacked velocity body under the seismic three-dimensional grid;

[0080] 2. The time-depth relationship obtained by well seismic calibration is one-dimensional data corresponding to time and depth;

[0081] 3. Adjust the stratigraphic order of the layers in chronological order and establish a stratigraphic structural framework;

[0082] 4. Interpolate the interpreted thinned horizons into fully covered horizons;

[0083] 5. Find the intersection point between the well trajectory and the interpreted layer to obtain the time and depth of the layer; retain it as the constraint point data;

[0084] (2) Establishing layer velocity model

[0085] Based on the seismic layer velocity modeling with layer control constraints, the structural framework of the area is first established according to the layers interpreted by seismic interpretation, and then the velocity field modeling is carried out considering the lateral and vertical changes of velocity on the basis of the structural framework.

[0086] The specific steps include: 1. According to the DIX formula, the stacked velocity body obtained by interpolation in the first step is converted into a layer velocity body;

[0087] 2. Extract the layer velocity along the layer frame from shallow layer to deep layer as the layer attribute;

[0088] 3. Extract the layer velocity trend surface on the layer and obtain the layer velocity change trend along the layer;

[0089] 4. Smooth the layer velocity on the layer so that the layer velocity along the layer is a relatively smooth velocity field and remove the distorted data in the initial layer velocity;

[0090] 5. According to the layer velocity trend surface, correct the smoothed layer velocity;

[0091] 6. Interpolate the interlayer velocity according to the depositional mode (syndeposition, top overlap, truncation, bottom overlap);

[0092] (3) Well calibration time domain model

[0093] The logging data is normalized by using the wellside logging data or the acoustic logging data obtained while drilling. A detailed layer velocity model is established for the target layer to realize real-time velocity modeling based on drilling constraints.

[0094] The specific steps include: 1. Preprocessing the acoustic logging by removing wild values ​​and interpolating missing values;

[0095] 2. Extract the compaction trend of the acoustic logging, and extend the top missing section of the acoustic logging based on the compaction trend;

[0096] 3. Analyze the distribution law of the target layer of logging data and perform standardized correction on acoustic logging;

[0097] 4. Extract the well bypass of the initial layer velocity model along the well trajectory;

[0098] 5. Perform low-frequency extraction on the acoustic logging to obtain the low-frequency curve of the acoustic logging, and correct the initial layer velocity of the well bypass according to the low-frequency curve;

[0099] 6. Obtain the correction data of all wells and perform volume correction on the initial interval velocity model;

[0100] 7. After well calibration, a more accurate velocity model can be obtained;

[0101] (4) Velocity inversion

[0102] The velocity body after well calibration is used as the initial model, and the model is used for constraint. Seismic information is added, and the weight coefficients of the model and seismic data are extracted. Velocity inversion is performed to obtain the fine layer velocity body, density body and impedance body.

[0103] The specific steps include: 1. extracting the wavelet of the seismic data based on the post-stack seismic data;

[0104] 2. Based on the wavelet, inversion parameters are extracted for the wellside velocity model trace of the known well;

[0105] 3. Determine the model modification amount and the weight coefficient of seismic data impact to ensure that the resolution of the velocity obtained by inversion meets the requirements;

[0106] 4. After determining the inversion parameters, perform generalized linear velocity inversion on the corrected layer velocity model;

[0107] (5) Speed ​​conversion and well average speed

[0108] In order to convert the fine layer velocity volume, seismic data volume, layer, fault file, etc. in the time domain into the depth domain, it is necessary to obtain the average velocity volume. The layer velocity volume, root mean square velocity volume, etc. are used for conversion to obtain the average velocity volume. Through the well time-depth data, the sedimentary mode of the seismic layer is selected, and the velocity field space correction is performed on the average velocity volume to obtain a better and more accurate average velocity volume.

[0109] The specific steps include: 1. Based on high-precision layer velocity, average velocity conversion is performed; 2. Time-depth relationship of known wells is extracted and average velocity is extracted;

[0110] 3. Along the well trajectory, the average velocity on the well is compared with the average velocity of the initial conversion to obtain the correction value of the average velocity, and the correction value is interpolated along the layer to obtain the average velocity correction value on the layer;

[0111] 4. According to the layer framework model, the average velocity correction amount on the layer is interpolated in three-dimensional space in turn to obtain a three-dimensional average velocity correction volume;

[0112] 5. Apply the three-dimensional average velocity correction body to the initial average velocity body to obtain a high-accuracy average velocity body;

[0113] (6) Time-depth conversion

[0114] Based on the established high-precision layer velocity field, average velocity field conversion can be performed. Using the average velocity body, layer velocity body, seismic data body, attribute body, layer, fault and other data can be quickly and accurately converted between the time domain and the depth domain.

[0115] The specific steps include:

[0116] 1. Under the control of high-precision and high-accuracy average velocity body, the velocity body and seismic attribute body in the time domain are converted to the depth domain in sequence;

[0117] 2. Under the control of the high-precision and high-accuracy average velocity body, the layers in the time domain are converted to the depth domain in sequence;

[0118] 3. Under the control of a high-precision and high-accuracy average velocity body, the faults in the time domain are converted to the depth domain in sequence.

[0119] The following are several specific embodiments of the present invention.

[0120] Example 1

[0121] In a specific embodiment 1 of the present invention, the velocity model correction method based on drilling constraints includes the following steps:

[0122] (1) Constructing an initial velocity model and building a velocity model based on the velocity spectrum;

[0123] (2) Establishing interlayer velocity model;

[0124] (3) Well calibration time domain model;

[0125] (4) Velocity inversion;

[0126] (5) Speed ​​conversion and well average speed.

[0127] Example 2

[0128] In the specific embodiment 2 of the present invention, the velocity model correction method based on drilling constraints includes the following steps:

[0129] (1) Constructing an initial velocity model based on the time-depth relationship of the well;

[0130] (2) Establishing interlayer velocity model;

[0131] (3) Well calibration time domain model;

[0132] (4) Velocity inversion;

[0133] (5) Speed ​​conversion and well average speed.

[0134] Example 3

[0135] In the specific embodiment 3 of the present invention, the velocity model correction method based on drilling constraints includes the following steps:

[0136] (1) Construct an initial velocity model based on the interval velocity where prestack depth migration is more accurate;

[0137] (2) Establishing interlayer velocity model;

[0138] (3) Well calibration time domain model;

[0139] (4) Velocity inversion;

[0140] (5) Speed ​​conversion and well average speed.

[0141] The velocity model established by this method has higher resolution and richer details than the velocity model established by traditional methods. This method fully combines seismic data and drilling data, and carries out targeted mutual constraints and corrections based on the characteristics of different types of data, so that the velocity model has a better match with the velocity and lithology measured on the well. The research on reservoir connectivity and stratum contact relationship based on the velocity model of this method has obtained results that are more in line with the actual underground situation, providing a reliable data basis for the efficient development of oil reservoirs.

[0142] Based on the velocity model correction technology, this method combines velocity spectrum and other data with drilling acoustic wave, VSP and other data under the constraints of structural and sequence models to correct the average velocity field and layer velocity field in the velocity model, thereby achieving more accurate time-depth conversion and providing a reliable data basis for various studies.

[0143] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0144] Except for the technical features described in the specification, all other technical features are known technologies to those skilled in the art.

Claims

1. A velocity model correction method based on drilling constraints, characterized in that: The velocity model correction method based on drilling constraints includes: Step 1, constructing an initial velocity model; Step 2, interpolating the layer velocity model through the velocity spectrum data; Step 3, well calibration time domain layer velocity model; Step 4, perform velocity inversion with model constraints; Step 5, perform speed conversion and calculate the average speed of the well calibration; Step 6, perform time-to-depth conversion using the average velocity after well calibration to obtain inversion layer velocity, seismic attribute volume, and layer data in the depth domain.

2. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 1, under the constraints of sequence stratigraphy, an initial velocity model is established by combining velocity spectrum data or fine well-seismic calibration time-depth relationship data.

3. The velocity model correction method based on drilling constraints according to claim 2, characterized in that: Step 1 includes: Step 11, interpolating the velocity spectrum into a stacked velocity volume under the seismic three-dimensional grid; Step 12: Well seismic calibration to obtain a time-depth relationship, which is one-dimensional data corresponding to time and depth; Step 13: adjusting the stratigraphic order of the layers in chronological order and establishing a stratigraphic structural framework; Step 14, interpolating the interpreted thinned horizon into a fully covered horizon; Step 15: Use the well trajectory and the interpreted layer data after interpolation to participate in the intersection calculation to obtain the time and depth at the layer; and retain it as the constraint point data.

4. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 2, seismic layer velocity modeling based on layer control constraints is carried out. First, the structural framework of the region is established according to the layers interpreted by the seismic interpretation. On the basis of the structural framework, velocity field modeling is carried out considering the lateral and vertical changes in velocity.

5. The velocity model correction method based on drilling constraints according to claim 4, characterized in that: Step 2 includes: Step 21, according to the DIX formula, the stacked velocity body obtained by interpolation in the first step is converted into a layer velocity body; Step 22, sequentially along the horizon frame, from the shallow horizon to the deep horizon, extracting the horizon velocity along the horizon as the horizon attribute; Step 23, extracting the layer velocity trend surface on the layer to obtain the layer velocity change trend along the layer; Step 24, smoothing the layer velocity on the layer, so that the layer velocity along the layer is a relatively smooth velocity field, and removing the distorted data in the initial layer velocity; Step 25, correcting the smoothed layer velocity according to the layer velocity trend surface; Step 26: perform interlayer velocity interpolation according to the depositional modes including syndeposition, top overlap, truncation, and bottom overlap.

6. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 3, the well logging data is normalized using the well logging data or the acoustic logging data obtained while drilling, and the fine layer velocity model established for the target layer is corrected to achieve real-time velocity modeling based on drilling constraints.

7. The velocity model correction method based on drilling constraints according to claim 6, characterized in that: Step 3 includes: Step 31, pre-processing the acoustic logging by removing wild values ​​and interpolating missing values; Step 32, extracting the compaction trend of the acoustic logging, and extending the top missing section of the acoustic logging according to the compaction trend; Step 33, analyzing the value range distribution law of the target layer segment of the logging data, and performing standardization correction on the acoustic logging; Step 34, extracting the well bypass of the initial layer velocity model along the well trajectory; Step 35, extracting low frequency of the acoustic logging to obtain a low frequency curve of the acoustic logging, and correcting the initial layer velocity of the well bypass channel according to the low frequency curve; Step 36, obtaining the correction data of all wells and performing volume correction on the initial interval velocity model; Step 37: After well calibration, a relatively accurate time domain interval velocity model can be obtained.

8. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 4, the velocity body after well calibration is used as the initial model, the model is used for constraint, seismic information is added, the weight coefficients of the model and seismic data are extracted, and velocity inversion is performed to obtain the fine layer velocity body, density body and impedance body.

9. The velocity model correction method based on drilling constraints according to claim 8, characterized in that: Step 4 includes: Step 41, extracting wavelets of the seismic data based on the post-stack seismic data; Step 42: Based on the wavelet, extract inversion parameters of the wellside velocity model trace of the known well; Step 43, determining the model modification amount and the seismic data impact weight coefficient to ensure that the resolution of the velocity obtained by inversion meets the requirements; Step 44: After the inversion parameters are determined, generalized linear velocity inversion is performed on the corrected layer velocity model.

10. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 5, the layer velocity body and the root mean square velocity body are converted to obtain the average velocity body; the sedimentary mode of the seismic layer is selected through the well time-depth data, and the velocity field space correction is performed on the average velocity body to obtain a better and more accurate average velocity body.

11. The velocity model correction method based on drilling constraints according to claim 10, characterized in that: Step 5 includes: Step 51: Perform average velocity conversion based on the high-precision layer velocity; Step 52, extracting the time-depth relationship of the known well and extracting the average velocity; Step 53: along the well trajectory, compare the average velocity on the well with the average velocity of the initial conversion to obtain a correction value of the average velocity, and interpolate the correction value along the layer to obtain the average velocity correction value on the layer; Step 54, according to the layer framework model, the average velocity correction amount on the layer is interpolated in three-dimensional space in sequence to obtain a three-dimensional average velocity correction volume; Step 55: Apply the three-dimensional average velocity correction volume to the initial average velocity volume to obtain a high-accuracy average velocity volume.

12. The velocity model correction method based on drilling constraints according to claim 1, characterized in that: In step 6, based on the established high-precision layer velocity field, average velocity field conversion can be performed. By using the average velocity body, the layer velocity body, seismic data body, attribute body, layer, and fault data can be quickly and accurately converted between the time domain and the depth domain.

13. The velocity model correction method based on drilling constraints according to claim 12, characterized in that: Step 6 includes: Step 61, under the control of the high-precision and high-accuracy average velocity volume, the velocity volume and the seismic attribute volume in the time domain are sequentially converted to the depth domain; Step 62, under the control of the high-precision and high-accuracy average velocity body, sequentially converting the layers in the time domain into the depth domain; Step 63: Under the control of the high-precision and high-accuracy average velocity body, the faults in the time domain are sequentially converted to the depth domain.

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