Method and device for modeling superficial layer in earth surface based on seismic wave data

Abstract

The invention discloses a method and device for modeling a superficial layer in an earth surface based on seismic wave data. The method includes the steps that seismic wave original data are preprocessed, a first model is obtained, the travel time and the offset distance of early-reached waves are determined based on the first model and the interesting depth; observation data about the early-reached waves are extracted from the original data according to the travel time and the offset distance; calculating data about the early-reached waves are generated according to the determined travel time ts and the determined offset distance on the basis of the first model; data field fitting is performed on the observation data and the calculating data so that the gradient can be obtained, and therefore a speed updating model is further obtained; the first model and the speed updating model are overlapped to obtain a second model, and the steps are executed repeatedly until the obtained speed updating model reaches the global optimum. Only part of early-reached wave information is used, nonlinearity of a target function is reduced, small offset distance information is adopted, error accumulation is reduced, and therefore by means of the method and device for modeling the superficial layer in the earth surface based on the seismic wave data, the global optimal solution can be converged more easily.

Description

technical field [0001] The invention relates to seismic exploration technology, in particular to a method and device for modeling the middle and shallow layers of the earth surface based on seismic wave data in seismic exploration. Background technique [0002] Seismic exploration is a geophysical exploration method that uses the difference in elasticity and density of underground media to infer the nature and shape of underground rock formations by observing and analyzing the response of the earth to artificially excited seismic waves. Seismic exploration is an important means of geological prospecting for petroleum, natural gas resources, and solid resources before drilling, and is widely used in coalfield and engineering geological exploration, regional geological research, and crustal research. [0003] The seismic wave is artificially excited on the surface, and when it propagates underground, it encounters a rock boundary with different medium properties. The seismic ...

AI Technical Summary

Problems solved by technology

However, there are still many limitations in the realization of this new method, such as the characteristics of large offset distance and low frequency information, etc., in order to use

Images