A land P-wave, converted S-wave channel sand body correlation interpretation method and system, electronic equipment and storage medium

Abstract

The present application provides a kind of land longitudinal wave, conversion transverse wave river channel sand body contrast interpretation method, system, electronic equipment and storage medium. Among them, method includes: the joint solution of longitudinal wave AVO attribute and conversion wave channel integration attribute is utilized comprehensively to solve river channel sand body identification and characterization, one is the effectiveness of conversion transverse wave to middle impedance sand body identification, to solve the problem of longitudinal wave to middle impedance sand body identification, to achieve the comprehensive identification of high, medium and low impedance sand body, expand the range of sand body identification.Two is the advantage of longitudinal resolution of longitudinal wave data, on the basis of lateral range determination, determine sand body period;Three is according to the wave peak horizon of channel integration, which represents sand body, the wave peak of longitudinal wave profile represents wave impedance interface, which is beneficial to sand body three-dimensional carving, improves the joint interpretation accuracy of multi-wave seismic data, and lays a foundation for subsequent effective solution of geological body description, reservoir sweet spot prediction and fluid detection.

Description

Technical Field

[0001] This invention belongs to the field of geophysical exploration technology, and in particular relates to a method, system, electronic equipment and storage medium for the comparative interpretation of longitudinal wave and converted transverse wave channel sand bodies on land. Background Technology

[0002] Tight sandstone gas (tight gas for short) falls under the category of unconventional natural gas. It currently represents the largest scale of unconventional natural gas development. In recent years, exploration and development of tight gas has seen rapid progress, both theoretically and technologically.

[0003] To support the goal of increasing reserves and production in this field, targeted technical research and applications were conducted using P-wave seismic data, achieving effective breakthroughs in areas such as amplitude-preserving and fidelity-preserving seismic data processing, and channel identification and characterization. However, with the deepening of application and actual drilling, it was found that the large velocity variations in tight sand bodies led to insufficient characterization of sand body boundaries by P-wave seismic data. Especially when the sandstone is a medium-impedance sand body, and its P-wave velocity is close to that of the surrounding mudstone, the P-wave seismic response exhibits weak reflection, which can easily be mistaken for "dark spots" or non-sand bodies and ignored, affecting the identification effect of sand bodies.

[0004] Land multi-wave exploration technology is an important technology that comprehensively utilizes P-waves and converted S-waves for oil and gas exploration. The key difference between it and conventional single P-wave exploration is that it uses a single source for excitation and a three-component geophone for reception, which can collect three-component wavefield information of underground geological targets. This provides the possibility for accurately describing the structural morphology of underground geological bodies, predicting fine fractures, and finely characterizing the spatial distribution of oil and gas reservoirs.

[0005] This technology has undergone more than forty years of development and application. It has certain advantages in lithology and reservoir identification, and is one of the effective means to improve the accuracy of exploration and development of complex oil and gas reservoirs such as tight and low-permeability reservoirs. Its technical advantages mainly include the following aspects:

[0006] (1) For areas such as gas cloud areas, clastic tight gas reservoirs, carbonate reservoirs, and shale oil and gas reservoirs, P-wave data has the characteristics of low signal-to-noise ratio and weak energy, while the converted S-wave information can be used to achieve accurate imaging and reservoir characterization.

[0007] (2) The wave field of multi-wave seismic exploration data on land can simultaneously obtain P-wave and converted S-wave wave field information. In addition to accurately extracting P-wave velocity parameters, it can also more accurately obtain S-wave velocity parameters, thereby further extracting accurate reservoir elastic parameters, such as Poisson's ratio, P-wave / S-wave velocity ratio, Young's modulus, brittleness index, etc., which can be used to carry out lithological prediction and reservoir characteristic description work.

[0008] (3) Converted shear waves are also shear waves in essence. They are more sensitive to reservoir fractures and can better solve the difficult problems of quantitatively predicting reservoir fracture development characteristics and fluid detection by utilizing shear wave splitting characteristics.

[0009] Therefore, in order to meet the high-precision exploration and development needs of the Shaximiao Formation channel-type tight lithologic gas reservoir, it is proposed to comprehensively utilize the advantages of P-waves and converted S-waves to finely characterize the spatial distribution of channel sand bodies, further supporting new breakthroughs in the exploration and development of tight gas in the Shaximiao Formation.

[0010] In terrestrial multi-wave seismic exploration, the joint comparative interpretation of P-waves and converted S-waves is a bottleneck restricting the development of this technology. This is especially true in characterizing tight gas channel sand bodies, where the two waves differ in kinematics and dynamics. Key differences include: P-wave velocity is higher than converted S-wave velocity, and propagation time is shorter; P-wave propagation is more susceptible to fluid influence, while converted S-waves propagate only within the rock framework and are less affected by fluids; P-waves have higher dominant frequencies and bandwidths than converted waves. Therefore, the two wave fields exhibit differences in their geophysical responses to channel sand bodies, including amplitude, phase changes, and longitudinal resolution. Establishing an interpretative bridge between the two waves is crucial for the application of this technology.

[0011] Currently, the commonly used method in tight gas channel interpretation mainly involves analyzing the well logging response characteristics of the target strata and target body based on well logging data, and then combining this with P-wave and converted-wave seismic profiles for synthetic record calibration. Based on the calibration results, strata interpretation and sandbody interpretation are then carried out separately. Finally, a planar or three-dimensional sandbody characterization is generated. In practical applications, this method has drawbacks: due to the different propagation times, seismic responses, and resolutions of the two wave fields, comparative interpretations are relatively independent, resulting in certain errors, low accuracy in channel sandbody characterization, and low efficiency of repeated comparative interpretations.

[0012] The above technical issues urgently need to be resolved. Summary of the Invention

[0013] To address the aforementioned technical problems, this invention proposes a method, system, electronic device, and storage medium for comparative interpretation of longitudinal waves and converted transverse waves in riverbed sand bodies.

[0014] The first aspect of this invention discloses a method for comparative interpretation of longitudinal waves and converted transverse waves in terrestrial channel sand bodies, the method comprising:

[0015] Step S1: Perform pre-stack time migration processing on the P-wave and converted S-wave seismic data to obtain the P-wave pre-stack time migration gather, P-wave profile, and converted S-wave profile.

[0016] Step S2: Load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target strata and sand bodies to obtain geological stratification;

[0017] Step S3: Using well logging curves, perform P-wave, converted wave and S-wave synthesis recording calibration; determine the time position of the geological strata at the well point used in the corresponding seismic profile;

[0018] Step S4: Based on the synthetic record calibration and the time location, clarify the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles;

[0019] Step S5: Based on the seismic response characteristics, perform target horizon tracking interpretation across the entire area on the P-wave profile and the converted S-wave profile;

[0020] Step S6: Perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation;

[0021] Step S7: Perform channel integral attribute calculations on the PG attribute data volume and the converted shear wave data volume respectively to obtain the PG channel integral data volume and the converted shear wave channel integral data volume;

[0022] Step S8: Based on the target stratigraphic tracking interpretation results, interpret the sand body stratigraphics based on the converted shear wave channel integral data volume, and save the converted shear wave sand body stratigraphic picking results;

[0023] Step S9: Based on the converted shear wave sand body layer picking results, project them onto the PG channel integral data volume, correct and supplement them on the PG channel integral data volume, and save the sand body layer picking results of the PG channel integral data volume.

[0024] Step S10: Project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the wave crests and troughs on the P-wave profile according to the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

[0025] According to the method of the first aspect of the present invention, in step S1, the method of performing pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles includes:

[0026] Static correction, noise attenuation, amplitude compensation and consistency processing, horizontal stacking and residual static correction processing, and pre-stack time migration processing and migration stacking are performed on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers and converted S-wave pre-stack time migration gathers.

[0027] The pre-stack time migration gathers of P-wave and converted S-wave are subjected to post-stack high-resolution and display optimization processing to obtain P-wave profiles and converted S-wave profiles.

[0028] According to the method of the first aspect of the present invention, in step S2, the method of using well logging curves to perform P-wave, converted wave, and S-wave synthesis recording calibration and determining the temporal position of the geological strata at the well point used on the corresponding seismic profile includes:

[0029] Based on the P-wave velocity, S-wave velocity, and density of the logging curve, the reflection time of each P-wave layer and the reflection time of each S-wave layer are calculated.

[0030] Spectral analysis of the target layer was conducted in the P-wave profile data and the converted S-wave profile data to determine the dominant frequency of the P-wave data and the dominant frequency of the converted S-wave data.

[0031] The dominant frequency values ​​of the P-wave data and the converted S-wave data are set separately. Two sub-waves of the dominant frequency of the P-wave data and the converted S-wave data are set separately. Theoretical synthesis records are made by combining the P-wave velocity, S-wave velocity and density values ​​in the logging curve.

[0032] By comparing and calibrating the synthetic records with the P-wave profile and the converted S-wave profile, the geological strata are projected onto the seismic profile, thereby clarifying the temporal position of the geological strata at the well point used in the seismic profile.

[0033] According to the method of the first aspect of the present invention, in step S4, the method for determining the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles based on the synthetic record calibration and the time position includes:

[0034] Check and match the geological strata with the gamma curve, porosity curve, clay content, and water saturation in the well logging curves;

[0035] Based on the matching results, the seismic response characteristics of P-waves and converted waves to the sand body are formed, including: the P-wave is a crest or trough, and the converted S-wave is a crest or trough; the P-wave amplitude is strong or weak, and the converted S-wave amplitude is strong or weak.

[0036] According to the method of the first aspect of the present invention, in step S5, the method for interpreting the target horizon tracking across the entire area based on the seismic response characteristics on the P-wave profile and the converted S-wave profile includes:

[0037] Based on the seismic response characteristics, stratigraphic interpretation was carried out at the locations of all well points within the work area;

[0038] Based on the stratigraphic interpretation of the well locations, stratigraphic interpretation of the seismic data from interconnected wells within the work area is carried out;

[0039] Based on the stratigraphic interpretation of the well-connected seismic data, stratigraphic picking was carried out in the work area using 80×80, 40×40, and 20×20 grids, and finally, the stratigraphic picking was densified and interpolated into a 1×1 grid.

[0040] According to the method of the first aspect of the present invention, in step S6, the method of performing AV0 attribute analysis on P-wave pre-stack time migration gather data, extracting intercept and gradient attributes, and obtaining PG attribute data volume by calculation includes:

[0041]

[0042] Where P represents the intercept; G represents the gradient attribute; PG represents the PG attribute data volume; v s Δv represents the transverse wave velocity. S ρ represents the difference in shear wave velocity between upper and lower strata; ρ represents density; Δρ represents the difference in density between upper and lower strata.

[0043] According to the method of the first aspect of the present invention, in step S7, the method of calculating the channel integral attributes of the PG attribute data volume and the converted shear wave data volume respectively to obtain the PG channel integral data volume and the converted shear wave channel integral data volume includes:

[0044]

[0045] Where Spg represents the PG trace integral data volume; PG(t) represents the PG attribute data volume; wpg(t) is the wavelet of the PG attribute data volume, and k is the reflection coefficient of the top interface;

[0046]

[0047] Where Sps represents the converted shear wave channel integral data volume; PS(t) represents the converted shear wave data volume; and wps(t) is the sub-wave of the converted shear wave data volume.

[0048] A second aspect of this invention discloses a comparative interpretation system for terrestrial P-wave and converted S-wave channel sand bodies, the system comprising:

[0049] The first processing module is configured to perform pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles.

[0050] The second processing module is configured to load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target formation and sand bodies to obtain geological stratification.

[0051] The third processing module is configured to use well logging curves to perform P-wave, converted wave and S-wave synthesis record calibration; and to determine the time position of the geological strata at the well point used in the corresponding seismic profile.

[0052] The fourth processing module is configured to, based on the synthetic record calibration and the time location, determine the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles.

[0053] The fifth processing module is configured to perform target horizon tracking interpretation across the entire area on the P-wave profile and the converted S-wave profile based on the seismic response characteristics.

[0054] The sixth processing module is configured to perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation.

[0055] The seventh processing module is configured to perform channel integral attribute calculations on the PG attribute data body and the converted shear wave data body respectively to obtain the PG channel integral data body and the converted shear wave channel integral data body.

[0056] The eighth processing module is configured to interpret the sand body layers based on the converted shear wave channel integral data volume, according to the results of the target layer tracking interpretation, and save the converted shear wave sand body layer picking results;

[0057] The ninth processing module is configured to project the transformed shear wave sand body layer picking results onto the PG channel integral data volume, perform corrections and supplements on the PG channel integral data volume, and save the sand body layer picking results of the PG channel integral data volume.

[0058] The tenth processing module is configured to project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the peaks and troughs of the P-wave profile based on the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

[0059] A third aspect of this invention discloses an electronic device. The electronic device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps in the method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to any one of the first aspects of this disclosure.

[0060] The fourth aspect of this invention discloses a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to any one of the first aspects of this disclosure.

[0061] In summary, the proposed scheme utilizes the theoretical basis of the correspondence between the PG attribute and converted shear wave in AVO analysis of P-wave seismic data, and the trace integral, which integrates seismic trace data to quickly obtain a relative wave impedance profile. This direct inversion method is an effective stratigraphic and lithological interpretation technique for tracking sand bodies, and it more easily distinguishes the sand body extent compared to the original profile. This establishes a new approach for integrated characterization of channel sand bodies using multi-wave data from terrestrial applications. It effectively establishes a joint P-wave and converted shear wave sand body identification and interpretation approach, fully utilizing information from both wavefields: firstly, it leverages the effectiveness of converted shear waves in identifying intermediate-impedance sand bodies, thus addressing the insufficient identification of intermediate-impedance sand bodies by P-waves, achieving comprehensive identification of high, medium, and low-impedance sand bodies and expanding the sand body identification range; secondly, it utilizes the high longitudinal resolution of P-wave data to determine the sand body phase based on the determined lateral extent. Compared with traditional methods, the implementation of this invention is more effective and convenient, with a reliable methodological basis and significant application results. It effectively solves the problem of accurate characterization of tight gas channel sand bodies in terrestrial multi-wave seismic exploration, enhancing the application value of this invention. Attached Figure Description

[0062] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0063] Figure 1 A flowchart illustrating a method for comparative interpretation of longitudinal and converted transverse wave channel sand bodies according to an embodiment of the present invention;

[0064] Figure 2 To characterize and represent sand bodies using longitudinal wave and converted transverse wave channel integral data according to embodiments of the present invention;

[0065] Figure 3 For longitudinal wave, converted transverse wave and trace integral sand body calibration according to embodiments of the present invention;

[0066] Figure 4 The sand body identification and characterization effect according to an embodiment of the present invention;

[0067] Figure 5 This is the depiction effect of river sand bodies according to an embodiment of the present invention;

[0068] Figure 6 This is a structural diagram of a land longitudinal wave and converted transverse wave channel sand body comparative interpretation system according to an embodiment of the present invention;

[0069] Figure 7 This is a structural diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0071] The first aspect of this invention discloses a method for comparative interpretation of longitudinal waves and converted transverse waves in riverbed sand bodies. Figure 1 This is a flowchart illustrating a method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to an embodiment of the present invention. Figures 1-5 As shown, the method includes:

[0072] Step S1: Perform pre-stack time migration processing on the P-wave and converted S-wave seismic data to obtain the P-wave pre-stack time migration gather, P-wave profile, and converted S-wave profile.

[0073] Step S2: Load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target strata and sand bodies to obtain geological stratification;

[0074] Step S3: Using well logging curves, perform P-wave, converted wave and S-wave synthesis recording calibration; determine the time position of the geological strata at the well point used in the corresponding seismic profile;

[0075] Step S4: Based on the synthetic record calibration and the time location, clarify the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles;

[0076] Step S5: Based on the seismic response characteristics, perform target horizon tracking interpretation across the entire area on the P-wave profile and the converted S-wave profile;

[0077] Step S6: Perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation;

[0078] Step S7: Perform channel integral attribute calculations on the PG attribute data volume and the converted shear wave data volume respectively to obtain the PG channel integral data volume and the converted shear wave channel integral data volume;

[0079] Step S8: Based on the target stratigraphic tracking interpretation results, interpret the sand body stratigraphics based on the converted shear wave channel integral data volume, and save the converted shear wave sand body stratigraphic picking results;

[0080] Step S9: Based on the converted shear wave sand body layer picking results, project them onto the PG channel integral data volume, correct and supplement them on the PG channel integral data volume, and save the sand body layer picking results of the PG channel integral data volume.

[0081] Step S10: Project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the wave crests and troughs on the P-wave profile according to the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

[0082] In step S1, pre-stack time migration processing is performed on the P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles.

[0083] In some embodiments, in step S1, the method of performing pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles includes:

[0084] Static correction, noise attenuation, amplitude compensation and consistency processing, horizontal stacking and residual static correction processing, and pre-stack time migration processing and migration stacking are performed on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers and converted S-wave pre-stack time migration gathers.

[0085] The pre-stack time migration gathers of P-wave and converted S-wave are subjected to post-stack high-resolution and display optimization processing to obtain P-wave profiles and converted S-wave profiles.

[0086] In step S2, P-wave profile data is loaded, S-wave profile data is converted, and well logging curves are loaded; geological stratification data of the target formation and sand bodies are loaded to obtain geological stratification.

[0087] Specifically, the loading logging curves mainly include P-wave velocity (Vp), S-wave velocity (Vs), density (ρ), gamma curve γ, and porosity curve. Clay content (Vsh) and water saturation (Sw).

[0088] In step S3, the P-wave, converted wave and S-wave composite records are calibrated using well logging curves; the time position of the geological strata at the well point used is determined on the corresponding seismic profile.

[0089] In some embodiments, in step S3, the method for using well logging curves to perform P-wave, converted wave, and S-wave synthesis recording calibration, and for determining the temporal location of the geological strata at the well point on the corresponding seismic profile, includes:

[0090] Based on the P-wave velocity, S-wave velocity, and density of the logging curve, the reflection time of each P-wave layer and the reflection time of each S-wave layer are calculated.

[0091] Spectral analysis of the target layer was conducted in the P-wave profile data and the converted S-wave profile data to determine the dominant frequency of the P-wave data and the dominant frequency of the converted S-wave data.

[0092] The dominant frequency values ​​of the P-wave data and the converted S-wave data are set separately. Two sub-waves of the dominant frequency of the P-wave data and the converted S-wave data are set separately. Theoretical synthesis records are made by combining the P-wave velocity, S-wave velocity and density values ​​in the logging curve.

[0093] By comparing and calibrating the synthetic records with the P-wave profile and the converted S-wave profile, the geological strata are projected onto the seismic profile, thereby clarifying the temporal position of the geological strata at the well point used in the seismic profile.

[0094] Specifically, methods for calculating the reflection times of each P-wave layer and each S-wave layer based on the P-wave velocity, S-wave velocity, and density of the well logging curve include:

[0095]

[0096] Among them, H p，i H represents the depth of the i-th layer of the P-wave. p，i+1 T represents the depth of the (i+1)th layer of the P-wave. p，i V is the reflection time of the i-th layer of the longitudinal wave. p，i+1 V is the longitudinal wave velocity of the (i+1)th layer. p,i Let be the longitudinal wave velocity of the i-th layer;

[0097]

[0098] Among them, H s，i H represents the depth of the i-th layer of the shear wave. s，i+1 T represents the depth of the (i+1)th layer of the shear wave. s，i V is the reflection time of the i-th layer of the transverse wave. s，i+1 V is the shear wave velocity of the (i+1)th layer. s,i Let be the transverse wave velocity of the i-th layer.

[0099] In step S4, based on the synthetic record calibration and the time location, the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles are determined.

[0100] In some embodiments, in step S4, the method for determining the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles based on synthetic record calibration and the time location includes:

[0101] Check and match the geological strata with the gamma curve, porosity curve, clay content, and water saturation in the well logging curves;

[0102] Based on the matching results, the seismic response characteristics of P-waves and converted waves to the sand body are formed, including: the P-wave is a crest or trough, and the converted S-wave is a crest or trough; the P-wave amplitude is strong or weak, and the converted S-wave amplitude is strong or weak.

[0103] In step S5, based on the seismic response characteristics, target horizon tracking interpretation is performed across the entire region on the P-wave profile and the converted S-wave profile.

[0104] In some embodiments, in step S5, the method for interpreting the target horizon across the entire region based on the seismic response characteristics on the P-wave profile and the converted S-wave profile includes:

[0105] Based on the seismic response characteristics, stratigraphic interpretation was carried out at the locations of all well points within the work area;

[0106] Based on the stratigraphic interpretation of the well locations, stratigraphic interpretation of the seismic data from interconnected wells within the work area is carried out;

[0107] Based on the stratigraphic interpretation of the well-connected seismic data, stratigraphic picking was carried out in the work area using 80×80, 40×40, and 20×20 grids, and finally, the stratigraphic picking was densified and interpolated into a 1×1 grid.

[0108] In step S6, AV0 attribute analysis is performed on the pre-stack time migration gather data of P-waves to extract the intercept and gradient attributes, and the PG attribute data volume is obtained by calculation.

[0109] In some embodiments, in step S6, the method of performing AV0 attribute analysis on P-wave pre-stack time-migrating gather data, extracting intercept and gradient attributes, and obtaining PG attribute data volume by calculation includes:

[0110]

[0111] Where P represents the intercept; G represents the gradient attribute; PG represents the PG attribute data volume; v s Δv represents the transverse wave velocity. S ρ represents the difference in shear wave velocity between upper and lower strata; ρ represents density; Δρ represents the difference in density between upper and lower strata.

[0112] Specifically, the P-wave pre-stack time-migrated gather Gather_P is transformed into P-wave angle-domain gather data Angel_P using the following formula:

[0113]

[0114] In this equation, V0 and k can be obtained by least squares fitting.

[0115]

[0116]

[0117] In the formula: x is the shot-receiver distance; Z is the depth of the target layer; n is the number of sampling points; v i ,z i These represent the velocity and depth of each sample point, respectively.

[0118] Based on the P-wave angle domain gather data, the intercept (P attribute) and gradient attribute (G attribute) of AVO attribute analysis are extracted along the target layer:

[0119] R(α)=P+G sin 2 α

[0120] P is the intercept of the equation of the line; G is the slope or gradient of the equation. Under certain assumptions, namely Δρ and Δv... P Δv S Relative to ρ and v respectively P v S It is relatively small, and v p / v s =2, therefore we get:

[0121]

[0122]

[0123] Calculate and obtain the PG attribute data body:

[0124]

[0125] In step S7, the PG attribute data volume and the converted shear wave data volume are respectively calculated using the channel integral attribute to obtain the PG channel integral data volume and the converted shear wave channel integral data volume.

[0126] In some embodiments, in step S7, the method of calculating the trace integral attributes of the PG attribute data volume and the converted shear wave data volume to obtain the PG trace integral data volume and the converted shear wave trace integral data volume includes:

[0127]

[0128] Where Spg represents the PG trace integral data volume; PG(t) represents the PG attribute data volume; wpg(t) is the wavelet of the PG attribute data volume, and k is the reflection coefficient of the top interface;

[0129]

[0130] Where Sps represents the converted shear wave channel integral data volume; PS(t) represents the converted shear wave data volume; and wps(t) is the sub-wave of the converted shear wave data volume.

[0131] In step S10, the sand body layer picking results of the PG channel integral data volume are projected onto the P-wave profile. Based on the sand body layer of the PG channel integral data volume, the top and bottom interfaces of the sand body are picked up along the peaks and troughs of the P-wave profile, and the interpretation and characterization of the top and bottom interfaces of the sand body are carried out.

[0132] Specifically, the top and bottom interfaces of the sand body are preserved; the three-dimensional characterization of the sand body is completed using the attribute interpretation and display functions.

[0133] In summary, the proposed scheme utilizes the theoretical basis of the correspondence between the PG attribute and converted shear wave in AVO analysis of P-wave seismic data, and the trace integral, which integrates seismic trace data to quickly obtain a relative wave impedance profile. This direct inversion method is an effective stratigraphic and lithological interpretation technique for tracking sand bodies, and it more easily distinguishes the sand body extent compared to the original profile. This establishes a new approach for integrated characterization of channel sand bodies using multi-wave data from terrestrial applications. It effectively establishes a joint P-wave and converted shear wave sand body identification and interpretation approach, fully utilizing information from both wavefields: firstly, it leverages the effectiveness of converted shear waves in identifying intermediate-impedance sand bodies, thus addressing the insufficient identification of intermediate-impedance sand bodies by P-waves, achieving comprehensive identification of high, medium, and low-impedance sand bodies and expanding the sand body identification range; secondly, it utilizes the high longitudinal resolution of P-wave data to determine the sand body phase based on the determined lateral extent. Compared with traditional methods, the implementation of this invention is more effective and convenient, with a reliable methodological basis and significant application results. It effectively solves the problem of accurate characterization of tight gas channel sand bodies in terrestrial multi-wave seismic exploration, enhancing the application value of this invention.

[0134] The second aspect of this invention discloses a comparative interpretation system for longitudinal and converted transverse wave channel sand bodies on land. Figure 6 This is a structural diagram of a land longitudinal wave and converted transverse wave channel sand body comparative interpretation system according to an embodiment of the present invention; as shown. Figure 6 As shown, the system 100 includes:

[0135] The first processing module 101 is configured to perform pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles and converted S-wave profiles.

[0136] The second processing module 102 is configured to load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target strata and sand bodies to obtain geological stratification.

[0137] The third processing module 103 is configured to use well logging curves to perform P-wave, converted wave and S-wave synthesis record calibration; and to determine the time position of the geological strata at the well point used in the corresponding seismic profile.

[0138] The fourth processing module 104 is configured to, based on the synthetic record calibration and the time position, determine the seismic response characteristics of different target layers and sand bodies on the P-wave profile and the converted S-wave profile.

[0139] The fifth processing module 105 is configured to perform target horizon tracking interpretation across the entire region on the P-wave profile and the converted S-wave profile based on the seismic response characteristics.

[0140] The sixth processing module 106 is configured to perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation.

[0141] The seventh processing module 107 is configured to perform channel integral attribute calculations on the PG attribute data body and the converted shear wave data body respectively to obtain the PG channel integral data body and the converted shear wave channel integral data body.

[0142] The eighth processing module 108 is configured to interpret the sand body layers based on the converted shear wave channel integral data volume, according to the result of the target layer tracking interpretation, and save the converted shear wave sand body layer picking result;

[0143] The ninth processing module 109 is configured to project the transformed shear wave sand body layer picking result onto the PG channel integral data volume, correct and supplement the PG channel integral data volume, and save the sand body layer picking result of the PG channel integral data volume.

[0144] The tenth processing module 110 is configured to project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the peaks and troughs of the P-wave profile based on the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

[0145] According to the system of the second aspect of the present invention, the first processing module 101 is specifically configured such that the method of performing pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles includes:

[0146] Static correction, noise attenuation, amplitude compensation and consistency processing, horizontal stacking and residual static correction processing, and pre-stack time migration processing and migration stacking are performed on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers and converted S-wave pre-stack time migration gathers.

[0147] The pre-stack time migration gathers of P-wave and converted S-wave are subjected to post-stack high-resolution and display optimization processing to obtain P-wave profiles and converted S-wave profiles.

[0148] According to the system of the second aspect of the present invention, the second processing module 102 is specifically configured to load well logging curves, mainly including P-wave velocity (Vp), S-wave velocity (Vs), density (ρ), gamma curve γ, and porosity curve. Clay content (Vsh) and water saturation (Sw).

[0149] According to the system of the second aspect of the present invention, the third processing module 103 is specifically configured to, using well logging curves, perform P-wave, converted wave, and S-wave synthetic recording calibration; and to determine the temporal position of the geological strata at the well point used on the corresponding seismic profile, include:

[0150] Based on the P-wave velocity, S-wave velocity, and density of the logging curve, the reflection time of each P-wave layer and the reflection time of each S-wave layer are calculated.

[0151] Spectral analysis of the target layer was conducted in the P-wave profile data and the converted S-wave profile data to determine the dominant frequency of the P-wave data and the dominant frequency of the converted S-wave data.

[0152] The dominant frequency values ​​of the P-wave data and the converted S-wave data are set separately. Two sub-waves of the dominant frequency of the P-wave data and the converted S-wave data are set separately. Theoretical synthesis records are made by combining the P-wave velocity, S-wave velocity and density values ​​in the logging curve.

[0153] By comparing and calibrating the synthetic records with the P-wave profile and the converted S-wave profile, the geological strata are projected onto the seismic profile, thereby clarifying the temporal position of the geological strata at the well point used in the seismic profile.

[0154] Specifically, methods for calculating the reflection times of each P-wave layer and each S-wave layer based on the P-wave velocity, S-wave velocity, and density of the well logging curve include:

[0155]

[0156] Among them, H p，i H represents the depth of the i-th layer of the P-wave. p，i+1 T represents the depth of the (i+1)th layer of the P-wave. p，iV is the reflection time of the i-th layer of the longitudinal wave. p，i+1 V is the longitudinal wave velocity of the (i+1)th layer. p,i Let be the longitudinal wave velocity of the i-th layer;

[0157]

[0158] Among them, H s，i H represents the depth of the i-th layer of the shear wave. s，i+1 T represents the depth of the (i+1)th layer of the shear wave. s，i V is the reflection time of the i-th layer of the transverse wave. s，i+1 V is the shear wave velocity of the (i+1)th layer. s,i Let be the transverse wave velocity of the i-th layer.

[0159] According to the system of the second aspect of the present invention, the fourth processing module 104 is specifically configured such that the method for determining the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles based on synthetic record calibration and the time position includes:

[0160] Check and match the geological strata with the gamma curve, porosity curve, clay content, and water saturation in the well logging curves;

[0161] Based on the matching results, the seismic response characteristics of P-waves and converted waves to the sand body are formed, including: the P-wave is a crest or trough, and the converted S-wave is a crest or trough; the P-wave amplitude is strong or weak, and the converted S-wave amplitude is strong or weak.

[0162] According to the system of the second aspect of the present invention, the fifth processing module 105 is specifically configured such that the method for performing full-area target horizon tracking interpretation on the P-wave profile and the converted S-wave profile based on the seismic response characteristics includes:

[0163] Based on the seismic response characteristics, stratigraphic interpretation was carried out at the locations of all well points within the work area;

[0164] Based on the stratigraphic interpretation of the well locations, stratigraphic interpretation of the seismic data from interconnected wells within the work area is carried out;

[0165] Based on the stratigraphic interpretation of the well-connected seismic data, stratigraphic picking was carried out in the work area using 80×80, 40×40, and 20×20 grids, and finally, the stratigraphic picking was densified and interpolated into a 1×1 grid.

[0166] According to the system of the second aspect of the present invention, the sixth processing module 106 is specifically configured such that the method for performing AV0 attribute analysis on P-wave pre-stack time migration gather data, extracting intercept and gradient attributes, and obtaining PG attribute data volume by calculation includes:

[0167]

[0168] Where P represents the intercept; G represents the gradient attribute; PG represents the PG attribute data volume; v s Δv represents the transverse wave velocity. S ρ represents the difference in shear wave velocity between upper and lower strata; ρ represents density; Δρ represents the difference in density between upper and lower strata.

[0169] Specifically, the P-wave pre-stack time-migrated gather Gather_P is transformed into P-wave angle-domain gather data Angel_P using the following formula:

[0170]

[0171] In this equation, V0 and k can be obtained by least squares fitting.

[0172]

[0173]

[0174] In the formula: x is the shot-receiver distance; Z is the depth of the target layer; n is the number of sampling points; v i ,z i These represent the velocity and depth of each sample point, respectively.

[0175] Based on the P-wave angle domain gather data, the intercept (P attribute) and gradient attribute (G attribute) of AVO attribute analysis are extracted along the target layer:

[0176] R(α)=P+G sin 2 α

[0177] P is the intercept of the equation of the line; G is the slope or gradient of the equation. Under certain assumptions, namely Δρ and Δv... P Δv S Relative to ρ and v respectively P v S It is relatively small, and v p / v s =2, therefore we get:

[0178]

[0179]

[0180] Calculate and obtain the PG attribute data body:

[0181]

[0182] According to the system of the second aspect of the present invention, the seventh processing module 107 is specifically configured to perform channel integral attribute calculations on the PG attribute data volume and the converted shear wave data volume respectively to obtain the PG channel integral data volume and the converted shear wave channel integral data volume, comprising:

[0183]

[0184] Where Spg represents the PG trace integral data volume; PG(t) represents the PG attribute data volume; wpg(t) is the wavelet of the PG attribute data volume, and k is the reflection coefficient of the top interface;

[0185]

[0186] Where Sps represents the converted shear wave channel integral data volume; PS(t) represents the converted shear wave data volume; and wps(t) is the sub-wave of the converted shear wave data volume.

[0187] A third aspect of this invention discloses an electronic device. The electronic device includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps in the method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to any one of the first aspects of this invention.

[0188] Figure 7 This is a structural diagram of an electronic device according to an embodiment of the present invention, such as... Figure 7 As shown, the electronic device includes a processor, memory, communication interface, display screen, and input device connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, Near Field Communication (NFC), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the device's casing, or an external keyboard, touchpad, or mouse.

[0189] Those skilled in the art will understand that Figure 7 The structure shown is merely a structural diagram of the part related to the technical solution of this disclosure and does not constitute a limitation on the electronic device to which the solution of this application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0190] A fourth aspect of this invention discloses a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to any one of the first aspects of this invention.

[0191] Please note that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The above embodiments only illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0192] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for comparative interpretation of longitudinal waves and converted transverse waves in terrestrial channel sand bodies, characterized in that, The method includes: Step S1: Perform pre-stack time migration processing on the P-wave and converted S-wave seismic data to obtain the P-wave pre-stack time migration gather, P-wave profile, and converted S-wave profile. Step S2: Load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target strata and sand bodies to obtain geological stratification; Step S3: Using well logging curves, perform P-wave, converted wave and S-wave synthesis recording calibration; determine the time position of the geological strata at the well point used in the corresponding seismic profile; Step S4: Based on the synthetic record calibration and the time location, clarify the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles; Step S5: Based on the seismic response characteristics, perform target horizon tracking interpretation across the entire area on the P-wave profile and the converted S-wave profile; Step S6: Perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation; Step S7: Perform channel integral attribute calculations on the PG attribute data volume and the converted shear wave data volume respectively to obtain the PG channel integral data volume and the converted shear wave channel integral data volume; Step S8: Based on the target stratigraphic tracking interpretation results, interpret the sand body stratigraphics based on the converted shear wave channel integral data volume, and save the converted shear wave sand body stratigraphic picking results; Step S9: Based on the converted shear wave sand body layer picking results, project them onto the PG channel integral data volume, correct and supplement them on the PG channel integral data volume, and save the sand body layer picking results of the PG channel integral data volume. Step S10: Project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the wave crests and troughs on the P-wave profile according to the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

2. The method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to claim 1, characterized in that, In step S1, the method for performing pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles includes: Static correction, noise attenuation, amplitude compensation and consistency processing, horizontal stacking and residual static correction processing, and pre-stack time migration processing and migration stacking are performed on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers and converted S-wave pre-stack time migration gathers. The pre-stack time migration gathers of P-wave and converted S-wave are subjected to post-stack high-resolution and display optimization processing to obtain P-wave profiles and converted S-wave profiles.

3. The method for comparative interpretation of longitudinal and converted transverse wave channel sand bodies according to claim 1, characterized in that, In step S3, the method of using well logging curves to perform P-wave, converted wave, and S-wave synthesis recording calibration, and determining the temporal location of the geological strata at the selected well point on the corresponding seismic profile, includes: Based on the P-wave velocity, S-wave velocity, and density of the logging curve, the reflection time of each P-wave layer and the reflection time of each S-wave layer are calculated. Spectral analysis of the target layer was conducted in the P-wave profile data and the converted S-wave profile data to determine the dominant frequency of the P-wave data and the dominant frequency of the converted S-wave data. The dominant frequency values ​​of the P-wave data and the converted S-wave data are set separately. Two sub-waves of the dominant frequency of the P-wave data and the converted S-wave data are set separately. Theoretical synthesis records are made by combining the P-wave velocity, S-wave velocity and density values ​​in the logging curve. By comparing and calibrating the synthetic records with the P-wave profile and the converted S-wave profile, the geological strata are projected onto the seismic profile, thereby clarifying the temporal position of the geological strata at the well point used in the seismic profile.

4. The method for comparative interpretation of terrestrial P-wave and converted S-wave channel sand bodies according to claim 1, characterized in that, In step S4, the method for determining the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles based on the synthetic record calibration and the time location includes: Check and match the geological strata with the gamma curve, porosity curve, clay content, and water saturation in the well logging curves; Based on the matching results, the seismic response characteristics of P-waves and converted S-waves to the sand body are formed, including: the P-wave is a crest or trough, and the converted S-wave is a crest or trough; the P-wave amplitude is strong or weak, and the converted S-wave amplitude is strong or weak.

5. The method for comparative interpretation of longitudinal and converted transverse wave channel sand bodies according to claim 1, characterized in that, In step S5, the method for interpreting the target horizon across the entire area based on the seismic response characteristics on the P-wave and converted S-wave profiles includes: Based on the seismic response characteristics, stratigraphic interpretation was carried out at the locations of all well points within the work area; Based on the stratigraphic interpretation of the well locations, stratigraphic interpretation of the seismic data from interconnected wells within the work area is carried out; Based on the stratigraphic interpretation of the well-connected seismic data, stratigraphic picking was carried out in the work area using 80×80, 40×40, and 20×20 grids, and finally, the stratigraphic picking was densified and interpolated into a 1×1 grid.

6. The method for comparative interpretation of longitudinal and converted transverse wave channel sand bodies according to claim 1, characterized in that, In step S6, the method for performing AV0 attribute analysis on the P-wave pre-stack time migration gather data, extracting the intercept and gradient attributes, and obtaining the PG attribute data volume through calculation includes: in, P Indicates the intercept attribute; G Represents gradient properties; PG Represents the PG attribute data body; v s Indicates the transverse wave velocity; This indicates the difference in shear wave velocity between upper and lower strata; Indicates density; This indicates the density difference between the upper and lower strata.

7. The method for comparative interpretation of longitudinal and converted transverse wave channel sand bodies according to claim 1, characterized in that, In step S7, the method of calculating the channel integral attributes of the PG attribute data volume and the converted shear wave data volume to obtain the PG channel integral data volume and the converted shear wave channel integral data volume includes: in, Represents the PG channel integral data volume; Represents the PG attribute data body; For the sub-wavelength of the PG attribute data volume, t is the reflection coefficient of the top interface; t0 represents the start time of the trace integral, and t represents the end time of the trace integral. in, This indicates the conversion of the transverse wave channel integral data volume; Indicates the converted shear wave data volume; For converting the transverse wave data volume into a sub-wave.

8. A system for comparative interpretation of longitudinal and converted transverse wave channel sand bodies on land, characterized in that, The system includes: The first processing module is configured to perform pre-stack time migration processing on P-wave and converted S-wave seismic data to obtain P-wave pre-stack time migration gathers, P-wave profiles, and converted S-wave profiles. The second processing module is configured to load P-wave profile data, convert S-wave profile data, and load well logging curves; load geological stratification data of the target formation and sand bodies to obtain geological stratification. The third processing module is configured to use well logging curves to perform P-wave, converted wave and S-wave synthesis record calibration; and to determine the time position of the geological strata at the well point used in the corresponding seismic profile. The fourth processing module is configured to, based on the synthetic record calibration and the time location, determine the seismic response characteristics of different target layers and sand bodies on the P-wave and converted S-wave profiles. The fifth processing module is configured to perform target horizon tracking interpretation across the entire area on the P-wave profile and the converted S-wave profile based on the seismic response characteristics. The sixth processing module is configured to perform AV0 attribute analysis on the pre-stack time migration gather data of P-waves, extract the intercept and gradient attributes, and obtain the PG attribute data volume through calculation. The seventh processing module is configured to perform channel integral attribute calculations on the PG attribute data body and the converted shear wave data body respectively to obtain the PG channel integral data body and the converted shear wave channel integral data body. The eighth processing module is configured to interpret the sand body layers based on the converted shear wave channel integral data volume, according to the results of the target layer tracking interpretation, and save the converted shear wave sand body layer picking results; The ninth processing module is configured to project the transformed shear wave sand body layer picking results onto the PG channel integral data volume, perform corrections and supplements on the PG channel integral data volume, and save the sand body layer picking results of the PG channel integral data volume. The tenth processing module is configured to project the sand body layer picking results of the PG channel integral data volume onto the P-wave profile, and pick the top and bottom interfaces of the sand body upward and downward along the peaks and troughs of the P-wave profile based on the sand body layer of the PG channel integral data volume, and perform interpretation and characterization of the top and bottom interfaces of the sand body.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, it implements the steps in the method for comparative interpretation of terrestrial longitudinal waves and converted transverse waves in channel sand bodies according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps in the method for comparative interpretation of terrestrial longitudinal waves and converted transverse waves in channel sand bodies according to any one of claims 1 to 7.

Images