Source location using time‐reverse imaging
Source location using time‐reverse imaging
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DOI：
10.1111/j.1365-2478.2010.00911.x
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发表时间：
2010-09
影响因子：
2.6
通讯作者：
B. Artman;I. Podladtchikov;B. Witten
中科院分区：
文献类型：
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作者：
B. Artman;I. Podladtchikov;B. Witten
我们提出了时间反演建模，图像空间波场分解和几个成像条件的链作为一个类似于迁移的算法，称为时间反演成像。该算法在被动地震数据中定位地下震源，在主动地震数据中定位绕射子。我们使用弹性传播利用多分量数据中可用的完整波形，虽然声学的例子。对于弹性的情况下，我们进行波场分解的图像域与空间导数计算P和S电位。为了定位源，通过提取自相关和互相关的零滞后来折叠时间轴，以返回物理空间中的图像。该算法的脉冲响应非常依赖于采集几何形状，并且需要在处理现场数据之前用点源进行评估。使用这些技术处理的带限数据可以成像源的辐射图案，而不仅仅是位置。我们提出了几种成像条件，但我们想象其他人可以被设计来调查有关源机制的性质的特定假设。我们说明了灵活的技术与合成的二维被动数据的例子和表面采集几何专门设计用于调查震颤类型的信号，不容易识别或解释在时域。
We present the chain of time‐reverse modeling, image space wavefield decomposition and several imaging conditions as a migration‐like algorithm called time‐reverse imaging. The algorithm locates subsurface sources in passive seismic data and diffractors in active data. We use elastic propagators to capitalize on the full waveforms available in multicomponent data, although an acoustic example is presented as well. For the elastic case, we perform wavefield decomposition in the image domain with spatial derivatives to calculate P and S potentials. To locate sources, the time axis is collapsed by extracting the zero‐lag of auto and cross‐correlations to return images in physical space. The impulse response of the algorithm is very dependent on acquisition geometry and needs to be evaluated with point sources before processing field data. Band‐limited data processed with these techniques image the radiation pattern of the source rather than just the location. We present several imaging conditions but we imagine others could be designed to investigate specific hypotheses concerning the nature of the source mechanism. We illustrate the flexible technique with synthetic 2D passive data examples and surface acquisition geometry specifically designed to investigate tremor type signals that are not easily identified or interpreted in the time domain.