中文摘要：

利用云南宽频带数字地震台网46个地震台连续记录的2008~2009年垂直向背景噪声,通过对台站对的背景噪声做互相关计算得到了台站间噪声互相关函数。基于互相关函数正负两个方向特性,分析云南地区5~10s、10~20s、20~40s共3个频段内高信噪比台站对的方位分布和季节变化特性,发现各个频段的优势方向均有差别,总体上看,云南地区的噪声源主要是来自近正东向和南南西向,可能受太平洋和印度洋的影响比较大。

英文摘要：

We obtain the cross-correlation function of noise by processing two years＇ ambient noise recorded by 46 broad-band,permanent stations of Yunnan Seismic Network.We measure the signal-to-noise ratio（SNR）of Rayleigh waves for positive and negative correlation time lags at different period bands（5-10s,10-20,and 20-40s）.we also determine the azimuthal distribution of the sources strong ambient-noise and seasonal variability.The principal directions of sources at different bands are different.Noise energy is dominant in the east and south-south west directions