Ambient Noise Interferometry from DAS Array in Underground Telecommunications Conduits
Ambient Noise Interferometry from DAS Array in Underground Telecommunications Conduits
复制标题
地下电信管道中 DAS 阵列的环境噪声干涉测量
DOI：
10.3997/2214-4609.201700743
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
S. Cole
中科院分区：
文献类型：
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作者：
E. Martin;B. Biondi;M. Karrenbach;S. Cole
总结环境噪声干涉测量使我们能够表征近地表的特征，而无需受控震源的成本和监管限制。地震检波器阵列的安装和维护成本可能很高，但沟槽分布式声学传感（DAS）阵列已显示出降低环境噪声采集维护成本的前景。在本文中，我们测试了一种新的，易于安装的采集系统，使用光纤在现有的地下电信管道的环境噪声收集在斯坦福大学校园。这种安装仅利用重力将光纤固定在充气导管中的适当位置，并且导管安装方法在整个现场有所不同。我们概述了DAS测量的环境噪声干涉测量的基本理论，提出了一种方法，使用附近的地震响应作为传感器耦合代理，并提出了信号处理方法，以应对各种噪声源在整个阵列。我们显示了互相关和色散计算沿着的一个子集的阵列预计主要产生瑞利波。
Summary Ambient noise interferometry allows us to characterize the near surface without the cost and regulatory constraints of controlled seismic sources. Geophone arrays can be expensive to install and maintain, but trenched distributed acoustic sensing (DAS) arrays have shown promise for reducing the maintenance cost of ambient noise acquisition. In this paper we test a novel, easily installed acquisition system using fibre in existing underground telecommunications conduits for ambient noise collection on the Stanford University campus. This installation only uses gravity to hold the fibre in place in the air-filled conduits, and the conduit installation method varies some throughout the site. We outline the basic theory of ambient noise interferometry for DAS measurements, present a method of using nearby earthquake response as a sensor coupling proxy, and present signal processing methods for coping with a variety of noise sources throughout the array. We show cross-correlations and dispersion calculations along a subset of the array expected to primarily yield Rayleigh waves.