Method and device for acquiring first-break wave ray

Abstract

The embodiment of the invention provides a method and device for acquiring a first-break wave ray. The method comprises the following steps: acquiring seismic data; according to the seismic data, establishing a layered velocity model; acquiring a layer thickness and a layer velocity in the velocity model, and according to the layer thickness and the layer velocity, acquiring the delayed time from trigger points to a target layer and from a receiving point to the target layer; according to the delayed time, the layer velocity, and the distance from each trigger point to the receiving point, acquiring the travelling time of the trigger point to the receiving point through each layer interface; comparing the travelling time, and taking the ray with the minimum travelling time as the first-break wave ray. Through the method and the device, provided by the embodiment of the invention, the first-break wave ray can be accurately acquired.

Description

technical field [0001] The invention relates to the technical field of geophysical prospecting, in particular to a method and device for obtaining first-arrival rays. Background technique [0002] The static correction processing technology in seismic exploration can be used to solve the problem that the change of seismic wave travel time in the near-surface medium affects the reflection wave stacking imaging. In static correction processing technology, first arrival is an important attribute of seismic data. In the process of seismic data processing, usually the attribute of first arrival can be used to solve the problem of static correction of seismic data. When an earthquake occurs, due to the different propagation speeds of various seismic waves, the time of propagation to the observation point is also sequential. The first wave received by the seismic observation point can be called the first arrival wave. [0003] Most of the near-surface models in the field are lay...

AI Technical Summary

Problems solved by technology

[0003] Most of the near-surface models in the field are layered, and the models used in current commercial software are regular grid models to be equivalent to layered models, and the velocity is continuous from shallow to deep. This ray tracing method It only adapts to the model of the continuous change of the velocity of the regular grid, but cannot adapt to the layered model of the sudden change of velocity, which is inconsistent with the actual surface conditions

Therefore, the first arrival rays cannot be obtained accurately, and a relatively accurate near-surface model cannot be inverted

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