期刊
GEOPHYSICAL JOURNAL INTERNATIONAL
卷 141, 期 1, 页码 157-174出版社
BLACKWELL SCIENCE LTD
DOI: 10.1046/j.1365-246X.2000.00070.x
关键词
body waves; Frechet derivatives; global seismology; ray theory; tomography; traveltime
We use body wave ray theory in conjunction with the Born approximation tocompute 3-D Frechet kernels for finite-frequency seismic traveltimes, measured by cross-correlation of a broad-band waveform with a spherical earth synthetic seismogram. Destructive interference among adjacent frequencies in the broad-band pulse renders a cross-correlation traveltime measurement sensitive only to the wave speed in a hollow banana-shaped region surrounding the unperturbed geometrical ray. The Frechet kernel expressing this sensitivity is expressed as a double sum over all forward-propagating body waves from the source and backward-propagating body waves from the receiver to every single scatterer in the vicinity of this central ray. The kernel for a differential traveltime, measured by cross-correlation of two phases at the same receiver, is simply the difference of the respective single-phase kernels. In the paraxial approximation, an absolute or differential traveltime kernel can be computed extremely economically by implementing a single kinematic and dynamic ray trace along each source-to-receiver ray.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据