Near-surface interbed multiple prediction method and device

Abstract

The invention discloses a near-surface interbed multiple prediction method and device. The method comprises the steps of collecting two-dimensional pre-stack seismic data of a research area; extracting all seismic traces of a common shot gather corresponding to a target seismic trace in a receiving point side predicted aperture and a common receiving point gather in a shot point side predicted aperture from the two-dimensional pre-stack seismic data; for each shot-receiver pair of which the shot point and the receiving point are respectively located in the shot point side and receiving point side predicted apertures, extracting a seismic trace in a corresponding common receiving point gather and a seismic trace in a corresponding common shot point gather respectively; for each shot-receiver pair, searching a downward reflection point with minimum fulfillment in a given search aperture on an interbed multiple interface, and determining a Green function of the downward reflection point;according to the two seismic traces and the Green function corresponding to each shot-receiver pair, predicting interlayer multiples of the shot-receiver pair; and adding all the predicted multiples of all possible shot-receiver pairs in the shot point side and receiving point side predicted apertures to obtain predicted multiples of the target seismic trace. The interbed multiples predicted by the method are wider in frequency band.

Description

technical field [0001] The invention relates to the field of oil and gas exploration, in particular to a method and device for predicting multiple waves between near-surface layers. Background technique [0002] This section is intended to provide a background or context to embodiments of the invention that are recited in the claims. The descriptions herein are not admitted to be prior art by inclusion in this section. [0003] With the continuous expansion of oil and gas exploration to new exploration areas and fields, surface and subsurface seismic geological conditions are becoming more and more diverse and complex, which makes seismic data processing face more and more challenges. Due to the strong energy, short period and early start time of the multiple waves between the onshore and near-surface layers, it will seriously interfere with the imaging of all effective waves in the shallow, intermediate and deep layers, and the low signal-to-noise ratio of shallow seismic ...

AI Technical Summary

Problems solved by technology

[0007] An embodiment of the present invention provides a method for predicting near-surface multiple waves, which is used to solve the technical problem that the existing inter-layer multiple wave prediction methods cannot be applied to near-surface or shallow layers. The method includes: collecting The two-dimensional pre-stack seismic data of the near-surface study area; for each selected target seismic trace, from the two-dimensional pre-stack seismic data, the common shot point gathers corresponding to the target seismic trace are extracted within the prediction aperture on the side of the receiving point and All seismic traces of the common receiver point gather within the predicted aperture on the shot point side; for each offset pair where the shot point and the receiver point are respectively located in the shot point side predicted aperture and the receiver point side predicted aperture, from the corresponding common shot point trace A seismic trace is extracted from the collection and common receiver point gathers; for each shot pair where the shot point and the receiver point are located in the predicted aperture on the side of the shot point and the predicted aperture on the side of the receiving point, respectively, the interlayer multiple wave interface is given In the specified search aperture, search for the downward reflection point at the time of minimum execution, and determine the Green's function of the offset pair; Yes, according to the Green's function of each offset pair and the two extracted seismic traces, the interlayer multiple waves of the offset pair are predicted; All the offsets in the aperture add up the predicted interlayer multiples to obtain the predicted interlayer multiples of the target seismic trace

[0008] An embodiment of the present invention also provides a near-surface interlayer multiple wave prediction device to solve the technical problem that the existing interlayer multiple wave prediction methods cannot be applied to near-surface or shallow layers. The device includes: The seismic data acquisition module is used to collect the two-dimensional pre-stack seismic data of the near-surface research area; the first data extraction module is used to extract the target seismic data from the two-dimensional pre-stack seismic data for each selected target seismic trace The corresponding common shot point gather is within the prediction aperture on the side of the receiving point and all the seismic traces of the common receiving point gather are within the prediction aperture on the side of the shot point; the second data extraction module is used for For each offset pair in the prediction aperture on the point side and the prediction aperture on the receiving point side, a seismic trace is extracted from the corresponding common shot point gather and common receiving point gather; the multiple wave interface Green's function determination module is used for The shot point and the receiving point are respectively located in each shot pair in the predicted aperture on the side of the shot point and the predicted aperture on the side of the receiving point, and the downward reflection point at the minimum performance is searched in the given search aperture on the interlayer multiple wave interface, And determine the Green's function of this shot-check pair; The shot-check pair multiple wave prediction module is used for each shot-check pair located in the shot point side prediction aperture and the receiving point side prediction aperture for the shot point and the receiving point respectively, according to each The Green's function of an offset pair and the two extracted seismic traces are used to predict the interlayer multiple waves of the offset pair; the seismic trace multiple wave prediction module is used to predict that the shot point and the receiving point are located on the side of the shot point All the offsets within the predicted aperture on the side of the aperture and the receiving point add up the predicted interlayer multiples to obtain the predicted interlayer multiples of the target seismic trace

[0009] The embodiment of the present invention also provides a computer device to solve the technical problem that the existing interlayer multiple wave prediction method cannot be applied to near-surface or shallow layers. The computer device includes a memory, a processor and a storage A computer program on the memory and operable on the processor, when the processor executes the computer program, the above-mentioned multiple wave prediction method between near-surface layers is realized

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