深源远震波形反演介质层状结构

在远场正演计算的基础上，运用３０°～９０°的四个不同深源远震记录波形，通过试错法选取台站下方的结构，借助波场反向重建算法，反演确定宜昌台站下方的速度结构。这一算法的实现有助于提高用试错法所得结果的可靠性和精确度，对于利用天然地震资料研究地球深部构造有一定的实用价值。

DETERMINING CRUSTAL AND UPPER MANTLE STRUCTURE BY INVERSION OF DEEP AND TELESEISMIC WAVEFORM

This paper is based on the algorithm of wave field reconstruction from the rate of the displacement spectrum of horizontal radial component of P wave to its vertical component.The observed data are selected from 4 teleseismic records of different depth at the Yichang Station with a good signal-noise ratio. After data preprocessing , the normalized seismograms wave worked out.Using trial-error method through comparison of the observed seismograms with synthetic seismograms ,the initial models of medium structure was determined. By use of the method of singular value decomposition,which is one of the inversion methods,the waveform is modeled and the velocity distribution of the crustal and upper mantle structure under Yichang Sation is finally obtained.