A Seismic Inversion Method Based on Waveform Slight Change Matching

Abstract

The invention discloses a seismic inversion method based on waveform micro-variation matching. Firstly, the positions of sparse sequences having large reflection coefficients are roughly searched, square wave processed impedance predicting sequences matched with seismic amplitude, phase and frequency are established through speed trend and compaction trend constraints by combining with reservoir prediction and hydrocarbon detection results, then the positions of sparse sequences having small reflection coefficients (or impedance predicting sequences) are determined through repeated iteration according to waveform micro-variation information, information such as the physical micro structure of the earth and micro-geological seismic response is fully mined, finally more accurate geological meaning is endowed to the formation by combining with physical analysis results of rocks to achieve accurate analysis on seismic waveform characteristics. In the inversion process, due to the fact thatreflection coefficients have stronger sparsity, inversion result interfaces have blocked characteristics (similar to square wave characteristics) and strong anti-noise capacity, and the readability of a formation interface is effectively improved.

Description

technical field

[0001] The invention relates to the technical field of oil and gas exploration, in particular to a seismic inversion method based on waveform micro-variation matching. Background technique

[0002] The fundamental task of oil and gas seismic exploration is to study and extract the physical parameters of the underground medium, such as velocity and density, based on various observed information, and to evaluate the oil and gas bearing properties of the reservoir. Seismic inversion, as a key technology for oil and gas exploration reservoir prediction and fine reservoir description, has solved the current geological problems at various stages of technology development and achieved good oil and gas exploration results. With the progress of exploration and development of oil and gas fields, marine basins generally develop reservoirs with complex structures, such as channels, beach bars, etc., with small single-layer thickness, rapid lateral changes, and complex di...

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