地震背景噪声中Lg波的提取

以鄂、湘、粤地区27个宽频带测震台站2 a的连续波形数据为例，对单台每日的连续波形数据进行去除仪器响应、去趋势、去均值、剔除地震事件和干扰及滤波（2.5~8 s）处理后，在互相关叠加数据中识别出了清晰的Lg波。另外，尝试通过叠加时间长度校正及用双台双震源法对几何扩散、噪声源强度的方位角变化和场地效应进行校正，并计算Q值。研究结果表明，对传统的地震背景噪声数据处理方法作适当修改后，噪声互相关叠加数据中可以提取出Lg波。

Extraction of Lg-Wave from Seismic Background Noise

In this study, taking the seismic waveform data of 27 broadband seismic stations in Hubei, Hunan and Guangdong as examples, we improve the traditional background noise data processing, replacing the time domain and spectral whitening by eliminating seismic events and interference. After we remove instrument response, mean, trend, seismic events and interference, and band-pass filter (2.5-8 s) from the daily waveform data of a single station, the clear Lg-wave is identified from the cross-correlation and temporal stack data. We try to recover the relative amplitude of the Lg-wave by cross-correlation and stack time length correction, azimuth and geometrical spreading correction and site responses by reverse two-station method/two-event method. The research of this paper shows that the Lg-wave can be extracted from seismic background noise.