摘要
以地震面波问题为例,提出P-SV波展平变换的精确求解方法,并以此为基础讨论了近似求解方法的适用性及适用范围.结果表明,展平变换指数m对最终结果没有显著影响,因此可选取任意值;在短波近似条件下,展平变换的近似解法是适当且合理的;展平变换的近似解法比精确解法的效率高一倍.对于频率较低的问题,应采用精确的求解方法.
Taking surface wave as an example,this paper proposed an exact solution of earth-flattening transformation for P-SV waves and discussed the applicability of the approximate methods.The results show that the transform parameter m has little influence on the final results,and on the condition of short wave approximation,approximate earth-flattening transformation is suitable.In addition,the efficiency of approximate transformation is twice of that of exact transformation.For low frequency problems we should use exact earth-flattening transformation.
引文
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