Generalized ray theory for shear dislocations
Generalized ray theory for shear dislocations
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DOI：
10.1785/bssa0640010045
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发表时间：
1974-02
影响因子：
3
通讯作者：
D. Helmberger
中科院分区：
文献类型：
--
作者：
D. Helmberger
由点源位错产生的 P、SH 和 SV 位移势的广义射线展开在分层半空间的表面进行评估。 Cagniard-de Hoop 技术用于获得瞬态响应。该分析的结果用于构建垂直断层面上剪切位错的合成地震图。博雷戈山地震（1968 年 4 月 9 日）远震距离的合成地震图与观测地震图的比较表明，等效点源深度为 9 公里，远场时间函数由具有指数衰减的阶跃函数近似。该时间函数适合 P 波形和 S 波形。正如一些研究人员所报告的，浅层事件的 P 波和 S 波之间角频率的明显变化可以通过表面反射来解释。
Generalized ray expansions of the P, SH, and SV displacement potentials resulting from a point-source dislocation are evaluated at the surface of a layered half-space. The Cagniard-de Hoop technique is used to obtain the transient response. The results of this analysis are used to construct synthetic seismograms for a shear dislocation on a vertical fault plane. Comparisons of synthetic and observed seismograms for the Borrego Mountain earthquake (April 9, 1968) at teleseismic distances indicate an equivalent point-source depth of 9 km with the far-field time function approximated by a step function with an exponential decay. This time function fits both the P and S wave forms. The apparent shift in corner frequency between the P and S waves for shallow events, as reported by some investigators, is explained by surface reflections.