利用超导重力数据探测内核超速旋转的研究

Study of Detecting the Inner Core Super Rotation Using SG Data

摘要: 内核存在约(0.27°~0.53°)/a的超速旋转,由此导致的全球年平均重力变化强度约为0.08~0.16μGal(0.8~1.6 nms-2)。除地震数据外,时变重力数据有可能成为探测内核超速旋转速率的重要信息源。对武汉九峰台站超导重力仪观测数据进行了潮汐改正、大气负荷改正、极移改正和日长变化改正,得到了经过各项改正后的时变重力信号;采用小波分析方法对上述时变重力信号进行了处理分析,得到了可供参考的结果;针对目前利用超导重力仪数据探测内核超速旋转所存在的困难提出了几个解决方案和建议。

Abstract: The inner core super rotation(ICSR) rate is 0.27°~0.53°/a,which gives rise to the annual average variation intensity about 0.08~0.16 μGal.Besides seismic data,temporary gravity data might become an important information source for detecting(ICSR).The influences caused by the tide,air pressure,polar motion and variation of the length of day,are drawn out from the gravity data recorded by the superconducting gravimeter(SG) at Jiufeng Station,Wuhan;and corrected temporary gravity signals are obtained.These temporary gravity signals are further analyzed by wavelet approach;and some valuble results are drawn out.Concerning the difficulties existed in detecting ICSR using SG data,some comments and proposals are provided.