Method, device, equipment, medium and product for seismic data correction

Abstract

The present application provides a method, device, equipment, medium and product for seismic data correction, which belongs to the technical field of comprehensive interpretation research of seismic data. The technical solution provided in the embodiment of the present application obtains the well seismic depth error gradient surface relationship corresponding to each well seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the well seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of consistency of the well seismic depth, providing accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks and prediction of remaining oil, thereby deepening the application of pre-stack depth migration seismic data in development blocks.

Description

Technical Field

[0001] The present application relates to the technical field of comprehensive interpretation research of seismic data, and in particular to a method, device, equipment, medium and product for seismic data correction. Background Art

[0002] In the process of comprehensive interpretation and research of seismic data, seismic exploration is usually carried out on the block to obtain seismic data. Through pre-stack depth migration, the geological structure is spatially repositioned to obtain continuous pre-stack depth migration seismic data in three-dimensional space. With the application of seismic data in oil and gas exploration, pre-stack depth migration seismic data is widely used in the detailed description of oil reservoirs and the prediction of remaining oil in development blocks. However, due to the large velocity errors in faults and slope zones, the well-seismic errors of pre-stack depth migration data are large, and the degree of consistency with the seismic depth of each layer is low, resulting in large errors in the subsequent detailed description of oil reservoirs and the prediction of remaining oil. Summary of the Invention

[0003] The present invention provides a method, device, equipment, medium, and product for seismic data correction, which can effectively eliminate errors in pre-stack depth migration seismic data, improve the consistency between pre-stack depth migration seismic data and drilling depth, and improve the degree of consistency between wellbore seismic depth. The technical solution is as follows:

[0004] In one aspect, a method for correcting seismic data is provided, the method comprising:

[0005] Based on the pre-stack depth migration seismic data of the block, at least one well-seismic reference layer is selected;

[0006] The pre-stack depth migration seismic data is processed multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction;

[0007] For any well-seismic reference layer, the least square method is used to obtain the corresponding well-seismic depth error gradient surface relationship;

[0008] For a first well seismic reference layer with the highest elevation among the at least one well seismic reference layer, correcting the pre-stack depth migration seismic data based on a well seismic depth error gradient surface relationship expression corresponding to the first well seismic reference layer;

[0009] If at least two seismic reference layers are selected, for any second seismic reference layer below the first seismic reference layer, after the seismic reference layers above the second seismic reference layer are calibrated, the seismic reference layer immediately after the previous calibration of the second seismic reference layer is obtained as the previous seismic reference layer. The calibration process for the second seismic reference layer includes:

[0010] Correcting the data below the previous well seismic reference layer in the prestack depth migration seismic data based on the well seismic depth error gradient surface relationship corresponding to the second well seismic reference layer;

[0011] A weighted average interpolation algorithm is used to process the well seismic depth error gradient surface relationship expression corresponding to the previous well seismic reference layer and the well seismic depth error gradient surface relationship expression corresponding to the second well seismic reference layer to obtain the corresponding weighted average relationship expression;

[0012] Based on the weighted average relationship, the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data are corrected.

[0013] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data.

[0014] In a possible implementation, for any well seismic reference layer, the least square method is used to obtain the corresponding well seismic depth error gradient surface relationship, including:

[0015] Based on the well seismic reference layer, multiple sample wells are obtained;

[0016] Acquiring well layer depth data of a plurality of sample wells;

[0017] The pre-stack depth migration seismic data of each sample well is used to subtract the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells;

[0018] Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0019] In a possible implementation, the pre-stack depth migration seismic data is corrected based on a well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, including:

[0020] The well-seismic depth error gradient surface relationship based on the first well-seismic reference layer is gridded to obtain the fitting depth error of each seismic trace in the grid. Based on the fitting depth error, depth correction is performed on the pre-stack depth migration seismic data corresponding to each seismic trace.

[0021] In one possible implementation, the method further includes:

[0022] At least one verification well is acquired, and the corrected pre-stack depth migration seismic data is verified based on the well layer depth data of the at least one verification well.

[0023] In one aspect, a device for correcting seismic data is provided, the device comprising:

[0024] A data acquisition module is used to select at least one well seismic reference layer based on pre-stack depth migration seismic data of the block;

[0025] A correction processing module is used to process the pre-stack depth migration seismic data multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction;

[0026] A relationship acquisition module is used to obtain the corresponding relationship of the seismic depth error gradient surface for any seismic reference layer using the least square method;

[0027] A correction module is configured to correct the pre-stack depth migration seismic data based on a seismic depth error gradient surface relationship expression corresponding to a first seismic reference layer having the highest elevation among the at least one seismic reference layer;

[0028] If at least two seismic reference layers are selected, for any second seismic reference layer below the first seismic reference layer, after the seismic reference layers above the second seismic reference layer are calibrated, the seismic reference layer immediately after the previous calibration of the second seismic reference layer is obtained as the previous seismic reference layer. The calibration process for the second seismic reference layer includes:

[0029] Correcting the data below the previous well seismic reference layer in the prestack depth migration seismic data based on the well seismic depth error gradient surface relationship corresponding to the second well seismic reference layer;

[0030] A weighted average interpolation algorithm is used to process the well seismic depth error gradient surface relationship expression corresponding to the previous well seismic reference layer and the well seismic depth error gradient surface relationship expression corresponding to the second well seismic reference layer to obtain the corresponding weighted average relationship expression;

[0031] Based on the weighted average relationship, the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data are corrected.

[0032] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data.

[0033] In one possible implementation, the relational expression acquisition module is configured to:

[0034] Based on the well seismic reference layer, multiple sample wells are obtained;

[0035] Acquiring well layer depth data of a plurality of sample wells;

[0036] The pre-stack depth migration seismic data of each sample well is used to subtract the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells;

[0037] Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0038] In one possible implementation, the correction module is configured to:

[0039] The well-seismic depth error gradient surface relationship based on the first well-seismic reference layer is gridded to obtain the fitting depth error of each seismic trace in the grid. Based on the fitting depth error, depth correction is performed on the pre-stack depth migration seismic data corresponding to each seismic trace.

[0040] In one possible implementation, the device further includes:

[0041] The verification module is used to obtain at least one verification well and verify the corrected pre-stack depth migration seismic data based on the well layer depth data of the at least one verification well.

[0042] In one aspect, an electronic device is provided, comprising:

[0043] one or more processors;

[0044] one or more memories for storing the one or more processor-executable instructions;

[0045] The one or more processors are configured to execute the instructions to implement the method for correcting seismic data as provided in any of the possible implementations described above.

[0046] On the one hand, a storage medium is provided, which, when instructions in the storage medium are executed by a processor of an electronic device, enables the electronic device to perform the method for correcting seismic data provided in any of the possible implementations described above.

[0047] In one aspect, a computer program product is provided, comprising computer instructions, which, when executed by a processor, implement the method for correcting seismic data provided in any one of the possible implementations described above.

[0048] The technical solution provided in the embodiment of the present application obtains the wellbore seismic depth error gradient surface relationship corresponding to each wellbore seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the wellbore seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of fit between the wellbore seismic depth and the wellbore seismic depth. It provides accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks, and remaining oil prediction, thereby deepening the application of pre-stack depth migration seismic data in development blocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0050] Figure 1 This is a flow chart of a method for correcting seismic data provided in an embodiment of the present application;

[0051] Figure 2 is a flow chart of another method for seismic data correction provided by an embodiment of the present application;

[0052] Figure 3 This is a synthetic record calibration diagram provided by this embodiment;

[0053] Figure 4 This is a scatter plot of the seismic depth error of the H1 layer provided in an embodiment of the present application;

[0054] Figure 5 This is a comparison diagram of the H1 layer error gradient surface and the structural surface provided in an embodiment of the present application;

[0055] Figure 6 This is a seismic profile of the H1 layer before error gradient surface correction provided in an embodiment of the present application;

[0056] Figure 7 This is a seismic profile of the H1 layer after error gradient surface correction provided in an embodiment of the present application;

[0057] Figure 8 is a statistical histogram of well-seismic errors before correction provided by an embodiment of the present application;

[0058] Figure 9 is a statistical histogram of well seismic errors after correction provided by an embodiment of the present application;

[0059] Figure 10 is a flow chart of another method for correcting seismic data provided in an embodiment of the present application;

[0060] Figure 11 This is a scatter plot of the seismic depth error of the H1 layer provided in an embodiment of the present application;

[0061] Figure 12 This is an H1 layer error gradient surface map provided in an embodiment of the present application;

[0062] Figure 13 This is a seismic profile of the H1 layer before error gradient surface correction provided in an embodiment of the present application;

[0063] Figure 14This is a seismic profile of the H1 layer after error gradient surface correction provided in an embodiment of the present application;

[0064] Figure 15 1 is a schematic structural diagram of a seismic data correction device provided in an embodiment of the present application;

[0065] Figure 16 This is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0066] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0067] Figure 1 This is a flow chart of a method for correcting seismic data provided in an embodiment of the present application. Figure 1 , the method can be applied to an electronic device, the method comprising:

[0068] 101. Based on the pre-stack depth migration seismic data of the block, select at least one well seismic reference layer.

[0069] 102. The prestack depth migration seismic data is processed multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction.

[0070] 1021. For any well-seismic reference layer, use the least squares method to obtain the corresponding well-seismic depth error gradient surface relationship.

[0071] 1022. Correction of pre-stack depth migration seismic data.

[0072] 10221. For the first well seismic reference layer with the highest altitude among at least one well seismic reference layer, correct the pre-stack depth migration seismic data based on the well seismic depth error gradient surface relationship formula corresponding to the first well seismic reference layer.

[0073] 10222. If at least two well seismic reference layers are selected, for any second well seismic reference layer below the first well seismic reference layer, based on the completion of the correction of the well seismic reference layer above the second well seismic reference layer, the well seismic reference layer after the previous correction of the second well seismic reference layer is obtained as the previous well seismic reference layer, and the second well seismic reference layer is corrected.

[0074] 102221. Based on the well-seismic depth error gradient surface relationship corresponding to the second well-seismic reference layer, correct the data below the depth of the previous well-seismic reference layer in the pre-stack depth migration seismic data.

[0075] 102222. A weighted average interpolation algorithm is used to process the well-seismic depth error gradient surface relationship expression corresponding to the previous well-seismic reference layer and the well-seismic depth error gradient surface relationship expression corresponding to the second well-seismic reference layer to obtain the corresponding weighted average relationship expression.

[0076] 102223. Based on the weighted average relationship, correct the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data.

[0077] The technical solution provided in the embodiment of the present application obtains the wellbore seismic depth error gradient surface relationship corresponding to each wellbore seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the wellbore seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of fit between the wellbore seismic depth and the wellbore seismic depth. It provides accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks, and remaining oil prediction, thereby deepening the application of pre-stack depth migration seismic data in development blocks.

[0078] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data.

[0079] In a possible implementation, for any well seismic reference layer, the least square method is used to obtain the corresponding well seismic depth error gradient surface relationship, including:

[0080] Based on the well seismic reference layer, multiple sample wells are obtained;

[0081] Acquiring well layer depth data of a plurality of sample wells;

[0082] The pre-stack depth migration seismic data of each sample well is used to subtract the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells;

[0083] Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0084] In a possible implementation, the pre-stack depth migration seismic data is corrected based on a well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, including:

[0085] The well-seismic depth error gradient surface relationship based on the first well-seismic reference layer is gridded to obtain the fitting depth error of each seismic trace in the grid. Based on the fitting depth error, depth correction is performed on the pre-stack depth migration seismic data corresponding to each seismic trace.

[0086] In one possible implementation, the method further includes:

[0087] At least one verification well is acquired, and the corrected pre-stack depth migration seismic data is verified based on the well layer depth data of the at least one verification well.

[0088] All of the above optional technical solutions can be combined in any way to form optional embodiments of the present application, and will not be described in detail here.

[0089] Figure 2 This is a flowchart of another method for correcting seismic data provided in an embodiment of the present application. Figure 2 The method can be applied to electronic equipment. The method details a case where a well seismic reference layer is selected in a block. The method includes:

[0090] 201. Based on the pre-stack depth migration seismic data of the block, select at least one well seismic reference layer.

[0091] In this step, the pre-stack depth migration seismic data of the block is processed by using the time domain of the pre-stack time migration seismic data to synthesize the records to calibrate the well-seismic layer correspondence, and select the relatively isochronous sequence interface with obvious well-seismic characteristics as the well-seismic reference layer in the pre-stack depth migration seismic data. The pre-stack depth migration seismic data in this step can be found in Figure 3 , Figure 3 This embodiment provides a synthetic record calibration diagram based on Figure 3 In the logging response curve, select the layer with obvious logging response characteristics as the well-seismic reference layer, for example, it can be H1, a well-seismic reference layer. Figure 3 In the middle, it is shown that above H1 is thick mudstone with high P-wave velocity, and below H1 is reservoir sandstone with low P-wave velocity.

[0092] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data. In subsequent steps, the well-seismic depth error gradient surface relationship expression of the two-dimensional data corresponds to a curve, and the well-seismic depth error gradient surface relationship expression of the three-dimensional data corresponds to a surface.

[0093] 202. Process the pre-stack depth migration seismic data, wherein the processing process includes obtaining a well-seismic depth error gradient surface relationship and correction.

[0094] In this embodiment, since there is only one well seismic reference layer, only one processing is required. The following describes the two steps of the processing in detail:

[0095] 2021. For the well-seismic reference layer, the least squares method is used to obtain the corresponding well-seismic depth error gradient surface relationship.

[0096] This step is used to perform error calculation based on the actually measured scattered well layer depth data of the sample wells and the corresponding pre-stack depth migration seismic data to obtain the errors of the pre-stack depth migration seismic data. These errors are caused by inaccurate velocity, and factors affecting velocity include faults, slope zones, etc. The well-seismic depth error gradient surface relationship obtained in this step can be used to eliminate the errors caused by inaccurate velocity.

[0097] This step specifically includes:

[0098] 20211. Based on the seismic benchmark layer of the well, multiple sample wells were obtained.

[0099] In this step, wells with obvious logging response characteristics of the base layer layer interface and accurate layer positions are selected as sample wells, so that the corresponding well layer depth data are more accurate.

[0100] 20212. Obtain well layer depth data for multiple sample wells.

[0101] The well layer depth data is the well layer depth data of the sample wells actually measured, which is scattered points.

[0102] 20213. The pre-stack depth migration seismic data of each sample well is subtracted from the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells.

[0103] The well seismic depth error can reflect the error of the pre-stack depth migration seismic data relative to the corresponding well layer depth data. The error can reflect the degree of offset between the pre-stack depth migration seismic data and the actual data at different locations, and can be used as the original data for subsequent correction.

[0104] In this embodiment, 180 sample wells can be selected in the block. By extracting the elevation depth of the H1 layer, the elevation of the seismic reference layer H1 is subtracted from the elevation of the well reference layer, and the well seismic depth errors of multiple sample wells on the reference layer H1 are calculated. Figure 4 This is a scatter plot of the seismic depth error of the H1 layer provided in an embodiment of the present application. Based on this scatter plot, the error conditions at different positions of the H1 layer can be clearly identified.

[0105] 20214. Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0106] The least squares method is a mathematical optimization technique that finds the best function matching data by minimizing the sum of squared errors. Least squares can be used to easily obtain unknown data and minimize the sum of squared errors between these obtained data and the actual data. This can then be used for surface fitting to obtain the gradient surface relationship between wellbore and seismic depth errors.

[0107] During the fitting process, interpolation is used to approximate discrete functions. Specifically, interpolation involves interpolating a continuous function based on discrete data points so that the continuous curve passes through all given discrete data points. Interpolation is an important method for approximating discrete functions. It allows us to estimate the approximate value of a function at a finite number of points based on the function's values at other points.

[0108] Specifically, using the structural surface as a constraint, the least squares method is used to interpolate the scattered points of the well-seismic error to obtain the well-seismic error gradient surface of the H1 layer. Figure 5 , Figure 5 This is a comparison diagram of the H1 layer error gradient surface and the structural surface provided in an embodiment of the present application, wherein: Figure 5 In the figure, a) is the error gradient surface of the H1 layer, and b) is the structural surface of the H1 layer. The error gradient surface contains systematic errors and random errors. It can be seen from the figure that the error gradient surface is consistent with the structural morphology. In the slope zone, the well-seismic depth error is negative. In the anticline area, the well-seismic depth error is relatively small. Near the fault, the well-seismic depth error increases.

[0109] 2022. Based on the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, the pre-stack depth migration seismic data is corrected.

[0110] The purpose of this correction step is to improve the accuracy of pre-stack depth migration seismic data and make the corrected data closer to the actual data for subsequent calculations.

[0111] In one possible implementation, the correction step includes: gridding the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, obtaining the fitting depth error of each seismic trace in the grid, and performing depth correction on the pre-stack depth migration seismic data corresponding to each seismic trace based on the fitting depth error.

[0112] In this step, the fitting depth error of each seismic trace is obtained through gridding, based on the fitting depth error of each seismic trace.

[0113] Based on the above-obtained well-seismic error gradient surface correction value, the pre-stack depth deviation seismic data is read through the program, and depth correction is performed on each depth sampling point one by one. Before correction, the well-seismic depth of the H1 layer is inconsistent. Figure 6 , Figure 6This is a seismic profile of the H1 layer before error gradient correction provided by the embodiment of the present application. After correction, the H1 layer seismic depth profile is consistent with the drilling depth. Among them, H101 well is a verification well, showing that the H1 layer well seismic depth is basically consistent. Figure 7 , Figure 7 This is a seismic profile of the H1 layer after error gradient surface correction provided in an embodiment of the present application.

[0114] In one possible implementation, the method further includes: acquiring at least one verification well, and verifying the corrected pre-stack depth migration seismic data based on well layer depth data of the at least one verification well.

[0115] This step can verify the accuracy of the method and provide a guarantee for the subsequent calculation process. In this embodiment, H101 can be set as the verification well. After correction, the well-seismic consistency is good ( Figure 6 and Figure 7 ), the well statistics H1 layer before correction has a large error in seismic depth, which includes systematic error and random error, see Figure 8 , Figure 8 This is a statistical histogram of well seismic error before correction provided by the embodiment of the present application. After correction, the well seismic depth error is reduced, which is mainly due to random error. Figure 9 , Figure 9 This is a statistical histogram of well-seismic errors after correction provided in an embodiment of the present application.

[0116] All of the above optional technical solutions can be combined in any way to form optional embodiments of the present application, and will not be described in detail here.

[0117] The technical solution provided in the embodiment of the present application obtains the wellbore seismic depth error gradient surface relationship corresponding to each wellbore seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the wellbore seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of fit between the wellbore seismic depth and the wellbore seismic depth. It provides accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks, and remaining oil prediction, thereby deepening the application of pre-stack depth migration seismic data in development blocks.

[0118] Figure 10 This is a flowchart of another method for correcting seismic data provided in an embodiment of the present application. Figure 10 The method can be applied to electronic equipment. The method details the case where two or more well seismic reference layers are selected in a block. The method includes:

[0119] 1001. Based on the pre-stack depth migration seismic data of the block, select at least one well seismic reference layer.

[0120] In this step, the pre-stack depth migration seismic data of the block is processed by using the time domain of the pre-stack time migration seismic data to synthesize the records to calibrate the well-seismic layer correspondence, and select the relatively isochronous sequence interface with obvious well-seismic characteristics as the well-seismic reference layer in the pre-stack depth migration seismic data. The pre-stack depth migration seismic data in this step can be found in Figure 3 , Figure 3 This embodiment provides a synthetic record calibration diagram based on Figure 3 In the logging response curve, the layers with obvious logging response characteristics are selected as the well-seismic reference layers, for example, the three well-seismic reference layers H1, H2 and H3 can be used. Figure 3 In the figure, it is shown that above H1 is thick mudstone with high P-wave velocity, below H1 is reservoir sandstone with low P-wave velocity, above base layer H2 is thick reservoir, below it is thin inter-reservoir, which is reflected by crest in pre-stack time-biased seismic, base layer H3 is reservoir bottom, below H3 is mudstone with high P-wave velocity, which is reflected by crest.

[0121] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data. In subsequent steps, the well-seismic depth error gradient surface relationship expression of the two-dimensional data corresponds to a curve, and the well-seismic depth error gradient surface relationship expression of the three-dimensional data corresponds to a surface.

[0122] 1002. The pre-stack depth migration seismic data is processed multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction.

[0123] The following is a detailed description of the two steps of this process:

[0124] 10021. For any well-seismic reference layer, use the least squares method to obtain the corresponding well-seismic depth error gradient surface relationship.

[0125] This step is used to perform error calculation based on the actually measured scattered well layer depth data of the sample wells and the corresponding pre-stack depth migration seismic data to obtain the errors of the pre-stack depth migration seismic data. These errors are caused by inaccurate velocity, and factors affecting velocity include faults, slope zones, etc. The well-seismic depth error gradient surface relationship obtained in this step can be used to eliminate the errors caused by inaccurate velocity.

[0126] This step specifically includes:

[0127] 100211. Based on the well seismic reference layer, multiple sample wells are obtained.

[0128] In this step, wells with obvious logging response characteristics of the base layer layer interface and accurate layer positions are selected as sample wells, so that the corresponding well layer depth data are more accurate.

[0129] 100212. Obtain well layer depth data for multiple sample wells.

[0130] The well layer depth data is the well layer depth data of the sample wells actually measured, which is scattered points.

[0131] 100213. Use the pre-stack depth migration seismic data of each sample well and subtract the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells.

[0132] The well seismic depth error can reflect the error of the pre-stack depth migration seismic data relative to the corresponding well layer depth data. The error can reflect the degree of offset between the pre-stack depth migration seismic data and the actual data at different locations, and can be used as the original data for subsequent correction.

[0133] In this embodiment, 180 sample wells can be selected in the block. By extracting the elevation depth of the H1 layer, the elevation of the seismic reference layer H1 is subtracted from the elevation of the well reference layer, and the well seismic depth errors of multiple sample wells on the reference layer H1 are calculated. Figure 11 This is a scatter plot of the seismic depth error of the H1 layer provided in an embodiment of the present application. Based on this scatter plot, the error conditions at different positions of the H1 layer can be clearly identified.

[0134] 100214. Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0135] The least squares method is a mathematical optimization technique that finds the best function matching data by minimizing the sum of squared errors. Least squares can be used to easily obtain unknown data and minimize the sum of squared errors between these obtained data and the actual data. This can then be used for surface fitting to obtain the gradient surface relationship between wellbore and seismic depth errors.

[0136] During the fitting process, interpolation is used to approximate discrete functions. Specifically, interpolation involves interpolating a continuous function based on discrete data points so that the continuous curve passes through all given discrete data points. Interpolation is an important method for approximating discrete functions. It allows us to estimate the approximate value of a function at a finite number of points based on the function's values at other points.

[0137] Specifically, using the structural surface as a constraint, the least squares method is used to interpolate the scattered points of the well-seismic error to obtain the well-seismic error gradient surface of the H1 layer. Figure 12 , Figure 12This is an H1 layer error gradient surface map provided in an embodiment of the present application.

[0138] 10022. Based on the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, correct the pre-stack depth migration seismic data.

[0139] The purpose of this correction step is to improve the accuracy of the data at the first seismic reference layer and above, so that the corrected data is closer to the actual data for subsequent calculations.

[0140] In one possible implementation, the correction step includes: gridding the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer, obtaining the fitting depth error of each seismic trace in the grid, and performing depth correction on the pre-stack depth migration seismic data corresponding to each seismic trace based on the fitting depth error.

[0141] In this step, the fitting depth error of each seismic trace is obtained through gridding, based on the fitting depth error of each seismic trace.

[0142] 10023. For any second well seismic reference layer below the first well seismic reference layer, after the well seismic reference layer above the second well seismic reference layer has been corrected, the well seismic reference layer after the previous correction of the second well seismic reference layer is obtained as the previous well seismic reference layer, and the second well seismic reference layer is corrected.

[0143] This embodiment details the case where two or more seismic reference layers are selected in a block. Therefore, if two seismic reference layers are selected, the previous seismic reference layer is the first seismic reference layer with the highest elevation in the block. That is, the previous seismic reference layer of H2 is H1, the previous seismic reference layer of H3 is H2, and so on.

[0144] The purpose of this correction step is to improve the accuracy of pre-stack depth migration data and make the corrected data closer to the actual data for subsequent calculations.

[0145] The correction process corresponding to the second well-seismic reference layer includes:

[0146] 100231. Based on the well-seismic depth error gradient surface relationship corresponding to the second well-seismic reference layer, correct the data below the depth of the previous well-seismic reference layer in the pre-stack depth migration seismic data.

[0147] The purpose of this correction step is to improve the accuracy of the data at the first seismic reference layer and above, so that the corrected data is closer to the actual data for subsequent calculations.

[0148] 100232. A weighted average interpolation algorithm is used to process the well-seismic depth error gradient surface relationship expression corresponding to the previous well-seismic reference layer and the well-seismic depth error gradient surface relationship expression corresponding to the second well-seismic reference layer to obtain the corresponding weighted average relationship expression.

[0149] For example, the pre-stack depth migration seismic data between the H1 layer and the H2 layer may be interpolated and calculated using a weighted average algorithm to correct the pre-stack depth migration seismic data of the H2 layer.

[0150] 100233. Based on the weighted average relationship, correct the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data.

[0151] Using the same method, the pre-stack depth migration seismic data of all layers are corrected in sequence, and finally the well-seismic data of all layers are consistent.

[0152] In one possible implementation, the correction step includes: gridding the well-seismic depth error gradient surface relationship equation based on the first well-seismic reference layer, obtaining a fitted depth error for each seismic trace in the grid, and performing depth correction on the prestack depth migration seismic data corresponding to each seismic trace based on the fitted depth error. In this step, the fitted depth error for each seismic trace is obtained through gridding, based on the fitted depth error for each seismic trace.

[0153] Based on the above-obtained well-seismic error gradient surface correction value, the pre-stack depth deviation seismic data is read through the program, and depth correction is performed on each depth sampling point one by one. Before correction, the well-seismic depth of the H1 layer is inconsistent. Figure 13 , Figure 13 This is a seismic profile of the H1 layer before error gradient correction provided by the embodiment of the present application. After correction, the H1 layer seismic depth profile is consistent with the drilling depth. Among them, H101 well is a verification well, showing that the H1 layer well seismic depth is basically consistent. Figure 14 , Figure 14 This is a seismic profile of the H1 layer after error gradient surface correction provided in an embodiment of the present application.

[0154] In one possible implementation, the method further includes: acquiring at least one verification well, and verifying the corrected pre-stack depth migration seismic data based on well layer depth data of the at least one verification well.

[0155] This step can verify the accuracy of the method and provide a guarantee for the subsequent calculation process. In this embodiment, H101 can be set as the verification well. After correction, the well-seismic consistency is good ( Figure 13 and Figure 14 ), the well statistics H1 layer before correction has a large error in seismic depth, which includes systematic error and random error ( Figure 8), after correction, the well seismic depth error is reduced, mainly due to random error ( Figure 9 ).

[0156] The technical solution provided in the embodiment of the present application obtains the wellbore seismic depth error gradient surface relationship corresponding to each wellbore seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the wellbore seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of fit between the wellbore seismic depth and the wellbore seismic depth. It provides accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks, and remaining oil prediction, thereby deepening the application of pre-stack depth migration seismic data in development blocks.

[0157] All of the above optional technical solutions can be combined in any way to form optional embodiments of the present application, and will not be described in detail here.

[0158] Figure 15 This is a schematic diagram of the structure of a seismic data correction device provided in an embodiment of the present application. Figure 15 , the device comprises:

[0159] The data acquisition module 1501 is used to select at least one well seismic reference layer based on the pre-stack depth migration seismic data of the block;

[0160] The correction processing module 1502 is used to process the pre-stack depth migration seismic data multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction;

[0161] The relational expression acquisition module 15021 is used to obtain the corresponding relational expression of the seismic depth error gradient surface for any seismic reference layer using the least square method;

[0162] The correction module 15022 is used to correct the first seismic reference layer with the highest altitude among the at least one seismic reference layer. The corresponding correction process includes:

[0163] Correcting the pre-stack depth migration seismic data based on the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer;

[0164] If at least two seismic reference layers are selected, for any second seismic reference layer below the first seismic reference layer, after the seismic reference layers above the second seismic reference layer are calibrated, the seismic reference layer immediately after the previous calibration of the second seismic reference layer is obtained as the previous seismic reference layer. The calibration process for the second seismic reference layer includes:

[0165] Correcting the data below the previous well seismic reference layer in the prestack depth migration seismic data based on the well seismic depth error gradient surface relationship corresponding to the second well seismic reference layer;

[0166] A weighted average interpolation algorithm is used to process the well seismic depth error gradient surface relationship expression corresponding to the previous well seismic reference layer and the well seismic depth error gradient surface relationship expression corresponding to the second well seismic reference layer to obtain the corresponding weighted average relationship expression;

[0167] Based on the weighted average relationship, the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data are corrected.

[0168] In one possible implementation, the pre-stack depth migration seismic data is two-dimensional data or three-dimensional data.

[0169] In one possible implementation, the relational expression acquisition module 15021 is configured to:

[0170] Based on the well seismic reference layer, multiple sample wells are obtained;

[0171] Acquiring well layer depth data of a plurality of sample wells;

[0172] The pre-stack depth migration seismic data of each sample well is used to subtract the corresponding well layer depth data to obtain the well seismic depth errors of multiple sample wells;

[0173] Based on the least squares method, the seismic depth errors of multiple sample wells are interpolated and fitted to obtain the gradient surface relationship of the seismic depth error.

[0174] In one possible implementation, the correction module 15022 is configured to:

[0175] The well-seismic depth error gradient surface relationship based on the first well-seismic reference layer is gridded to obtain the fitting depth error of each seismic trace in the grid. Based on the fitting depth error, depth correction is performed on the pre-stack depth migration seismic data corresponding to each seismic trace.

[0176] In one possible implementation, the device further includes:

[0177] The verification module is used to obtain at least one verification well and verify the corrected pre-stack depth migration seismic data based on the well layer depth data of the at least one verification well.

[0178] It should be noted that the apparatus for triggering intelligent network services provided in the above embodiments uses the division of the functional modules described above as an example only. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the apparatus for seismic data correction provided in the above embodiments and the method for seismic data correction are based on the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0179] The technical solution provided in the embodiment of the present application obtains the wellbore seismic depth error gradient surface relationship corresponding to each wellbore seismic reference layer through the least squares method, and corrects the pre-stack depth migration seismic data corresponding to the wellbore seismic reference layer layer by layer, effectively eliminating the error of the pre-stack depth migration seismic data, making the pre-stack depth migration seismic data more consistent with the drilling depth, and improving the degree of fit between the wellbore seismic depth and the wellbore seismic depth. It provides accurate basic data for directly using pre-stack depth migration seismic data for horizontal well drilling, detailed description of oil reservoirs in development blocks, and remaining oil prediction, thereby deepening the application of pre-stack depth migration seismic data in development blocks.

[0180] Figure 16 1 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device 1600 may have relatively large differences due to different configurations or performances, and may include one or more processors (central processing units, CPU) 1601 and one or more memories 1602, wherein the memory 1602 stores at least one program code, and the at least one program code is loaded and executed by the processor 1601 to implement the methods provided in the above-mentioned various method embodiments. Of course, the electronic device may also have components such as a wired or wireless network interface, a keyboard, and an input / output interface for input and output. The electronic device may also include other components for implementing device functions, which will not be described in detail here.

[0181] In some embodiments, the computer program involved in the embodiments of the present application may be deployed and executed on an electronic device, or on multiple electronic devices located at one location, or on multiple electronic devices distributed at multiple locations and interconnected through a communication network. Multiple electronic devices distributed at multiple locations and interconnected through a communication network may constitute a blockchain system.

[0182] In an exemplary embodiment, a computer-readable storage medium is also provided, such as a memory including program code. The program code can be executed by a processor in an electronic device to perform the seismic data correction method described in the above embodiment. For example, the computer-readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc (CD-ROM), a magnetic tape, a floppy disk, or an optical data storage device.

[0183] Those skilled in the art will understand that all or part of the steps of implementing the above embodiments can be completed by hardware or by instructing related hardware through a program. The above program can be stored in a computer-readable storage medium, and the above-mentioned storage medium can be a read-only memory, a disk or an optical disk, etc.

[0184] In an exemplary embodiment, a computer program product is further provided, comprising computer instructions, which, when executed by a processor, implement the method for correcting seismic data provided in any of the possible implementations described above.

[0185] The above are only optional embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for correcting seismic data, characterized in that: The method comprises: Based on the pre-stack depth migration seismic data of the block, at least one well-seismic reference layer is selected; Processing the pre-stack depth migration seismic data multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction; For any well-seismic reference layer, the least square method is used to obtain the corresponding well-seismic depth error gradient surface relationship; For a first well seismic reference layer with the highest elevation among the at least one well seismic reference layer, correcting the pre-stack depth migration seismic data based on a well seismic depth error gradient surface relationship expression corresponding to the first well seismic reference layer; If at least two seismic reference layers are selected, for any second seismic reference layer below the first seismic reference layer, after the seismic reference layer above the second seismic reference layer is calibrated, the seismic reference layer immediately preceding the calibration of the second seismic reference layer is obtained as the previous seismic reference layer. The calibration process for the second seismic reference layer includes: Correcting the data below the previous well seismic reference layer in the prestack depth migration seismic data based on the well seismic depth error gradient surface relationship corresponding to the second well seismic reference layer; A weighted average interpolation algorithm is used to process the well seismic depth error gradient surface relationship expression corresponding to the previous well seismic reference layer and the well seismic depth error gradient surface relationship expression corresponding to the second well seismic reference layer to obtain the corresponding weighted average relationship expression; Based on the weighted average relationship, the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data are corrected.

2. The method according to claim 1, characterized in that The pre-stack depth migration seismic data is two-dimensional data or three-dimensional data.

3. The method according to claim 1, characterized in that For any well seismic reference layer, the least square method is used to obtain the corresponding well seismic depth error gradient surface relationship, which includes: Based on the well seismic reference layer, a plurality of sample wells are obtained; Acquiring well layer depth data of a plurality of the sample wells; Using the pre-stack depth migration seismic data of each sample well, subtracting the corresponding well layer depth data, to obtain the well seismic depth errors of the plurality of sample wells; Based on the least square method, the seismic depth errors of the plurality of sample wells are interpolated and fitted to obtain a seismic depth error gradient surface relationship expression.

4. The method according to claim 1, wherein The method of correcting the pre-stack depth migration seismic data based on the well-seismic depth error gradient surface relationship corresponding to the first well-seismic reference layer includes: The well-seismic depth error gradient surface relationship expression corresponding to the first well-seismic reference layer is gridded to obtain the fitting depth error of each seismic trace in the grid, and based on the fitting depth error, depth correction is performed on the pre-stack depth migration seismic data corresponding to each seismic trace.

5. The method according to claim 1, wherein The method further comprises: At least one verification well is acquired, and the corrected pre-stack depth migration seismic data is verified based on the well layer depth data of the at least one verification well.

6. A device for correcting seismic data, characterized in that: The device comprises: A data acquisition module is used to select at least one well seismic reference layer based on pre-stack depth migration seismic data of the block; A correction processing module is used to process the pre-stack depth migration seismic data multiple times in the order of the well-seismic reference layer from top to bottom, wherein each processing process includes obtaining the well-seismic depth error gradient surface relationship and correction; A relationship acquisition module is used to obtain the corresponding relationship of the seismic depth error gradient surface for any seismic reference layer using the least square method; A correction module is configured to correct the pre-stack depth migration seismic data based on a seismic depth error gradient surface relationship expression corresponding to a first seismic reference layer having the highest elevation among at least one seismic reference layer; If at least two seismic reference layers are selected, for any second seismic reference layer below the first seismic reference layer, after the seismic reference layer above the second seismic reference layer is calibrated, the seismic reference layer immediately preceding the calibration of the second seismic reference layer is obtained as the previous seismic reference layer. The calibration process for the second seismic reference layer includes: Correcting the data below the previous well seismic reference layer in the prestack depth migration seismic data based on the well seismic depth error gradient surface relationship corresponding to the second well seismic reference layer; A weighted average interpolation algorithm is used to process the well seismic depth error gradient surface relationship expression corresponding to the previous well seismic reference layer and the well seismic depth error gradient surface relationship expression corresponding to the second well seismic reference layer to obtain the corresponding weighted average relationship expression; Based on the weighted average relationship, the data between the previous well seismic reference layer and the second well seismic reference layer in the pre-stack depth migration seismic data are corrected.

7. The device according to claim 6, characterized in that The relational expression acquisition module is used to: Based on the well seismic reference layer, a plurality of sample wells are obtained; Acquiring well layer depth data of a plurality of the sample wells; Using the pre-stack depth migration seismic data of each sample well, subtracting the corresponding well layer depth data, to obtain the well seismic depth errors of the plurality of sample wells; Based on the least square method, the seismic depth errors of the plurality of sample wells are interpolated and fitted to obtain a seismic depth error gradient surface relationship expression.

8. An electronic device, characterized in that: include: one or more processors; one or more memories for storing the one or more processor-executable instructions; The one or more processors are configured to execute the instructions to implement the method for correcting seismic data according to any one of claims 1 to 5.

9. A storage medium, characterized in that: When the instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the method for correcting seismic data according to any one of claims 1 to 5.

10. A computer program product comprising computer instructions, characterized in that When the computer instructions are executed by a processor, the method for correcting seismic data according to any one of claims 1 to 5 is implemented.

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