Elastic reverse time migration imaging method by combining seismic multi-component

Abstract

The invention discloses an elastic reverse time migration imaging method by combining seismic multi-component and belongs to the field of exploration geophysics. The method comprises the following steps: directly inputting seismic multi-component data; without performing the wave field separation on the input data, extrapolating forwards at inverse time based on an elastic wave equation; building an underground elastic vector seismic wave field by combining with multi-component; acquiring four elastic wave imaging results having specific physical significance, such as longitudinal wave, transverse wave, transition longitudinal wave and transition transverse wave, by applying an elastic wave cross-correlation imaging condition of lighting compensation; and suppressing the low wave number noise in the elastic reverse time migration by performing low-pass angle filtering, thereby acquiring an imaging result of final elastic wave migration. By directly inputting the seismic multi-component data and building the underground elastic vector seismic wave field by combining with multi-component, the method can be used for accurately imaging for complex earth medium.

Description

1. Technical field: [0001] The invention relates to the field of exploration geophysics, in particular to a seismic multi-component joint elastic reverse time migration imaging method. 2. Background technology: [0002] With the in-depth development of seismic exploration, the target of oil and gas exploration is gradually shifting to the direction of complex surface, complex structure and complex reservoir, which puts forward higher requirements for the precision of seismic imaging. At present, in oil and natural gas seismic exploration, the longitudinal wave exploration method is still the main method. However, the wave field propagating in the earth medium is not limited to the longitudinal wave, but also the shear wave and converted wave. That is to say, the seismic wave field is an elastic wave field, so the migration imaging technology based on the elastic wave equation can be better Accurately characterize the Earth medium. Based on this, elastic seismic migration i...

AI Technical Summary

Problems solved by technology

Second, the elastic vector feature of multi-component data is ignored

Using scalar wave processing technology will inevitably lose the above characteristics

Therefore, based on this conventional processing method, it is impossible to solve the energy conversion between different subsets of signals (longitudinal wave and shear wave), let alone guarantee the accuracy and physical meaning of the imaging amplitude.

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