地震对IGS基准站坐标时序噪声特性的影响

Influence of Earthquakes on the Noise Characteristics of IGS Reference Station Coordinate Time Series

选取日本7个IGS基准站在2011-03-11东日本大地震前后各3a的坐标时间序列,计算此区域的共模误差,利用CATS软件确定地震前后基准站各分量的最优噪声模型,分析共模误差和东日本大地震对基准站坐标时序噪声特性的影响。结果表明,共模误差在N、E、U方向均表现出较为明显的周期特性,且地震的发生导致其N、U方向均值分别增大2.1倍和1.5倍;利用空间滤波的方法剔除共模误差后,水平方向的闪烁噪声得到较明显的削弱;IGS基准站各分量表现出不同的噪声特性,其变化因站而异,并未表现出明显的规律;地震对基准站坐标时序噪声的影响主要表现为BP、FN和RW特性,且距离震中越近,这种影响越明显。

Focusing on the coordinate time series captured from 7 Japanese IGS reference stations in the three years before and after the March 11, 2011, east Japan earthquake, the common mode error of this region is calculated. Furthermore, the optimal noise model of each station components before and after the earthquake are determined using CATS software, so the noise characteristics can be ana- lyzed based on the common mode error of the east Japan earthquake. The conclusion is drawn that ob- vious periodicity shows in the common mode error in N, E, U direction, and the mean value in N, U direction increases 2.1 times and 1.5 times due to the earthquake. Using the spatial filtering method to eliminate the common mode error, the flicker noise in the horizontal direction is obviously weak- ened. Each component of IGS reference stations presents diverse noise characteristics, with no obvi- ous regularity. The influence of the earthquake on reference station coordinate time series noise is mainly on BP, FN and RW characteristics, and the closer to the epicenter of the earthquake, the more obvious the effect will be.