摘要
地震干涉技术可以将任意2个检波器接收到的数据合成为在若干检波器之间传播的波,就好像其中的一个检波器作为一个虚拟震源来发挥作用。它可以从混沌无序的地震信号中发现有用信息,从地震噪声中提取有用信号以此推断地震波穿过介质的地质构造。基于反褶积算法,对其理论公式进行了较详细的推导,实现被动源地震干涉成像,证明了反褶积算法的可行性;并将其结果与互相关算法的结果进行对比,分析了2种方法在信噪比和分辨率方面的差异。数值计算表明,反褶积算法的纵向分辨率比互相关算法的高。对其进行的加噪试算表明,震源叠加后的反褶积算法呈现出高信噪比的特点。
Seismic interferometry allows us from records at any two receivers to synthesize waves that propagate between the receivers as if one of the receivers behaves as a source.From chaotic disorder seismic signals,this method can extract useful information,which can be used to infer the geological structure.Based on the theory of deconvolution seismic interferometry,the authors have made a more detailed derivation for the imaging formula.The implementation of imaging method demonstrates the feasibility of deconvolution algorithm in passive source seismic interferometry.We also compare the signal-to-noise ratio and resolution from deconvolution method with cross-correlation algorithm.More numerical calculations show that the vertical resolution from deconvolution is higher than cross-correlation,method and after summation over sources deconvolution has a high signal to noise ratio.
引文
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