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基于全球分布的14个台站GWR超导重力仪21个高精度潮汐重力观测系列(约86年),检测了地球固态内核平动振荡现象.将观测数据分成G-Ⅰ组(8个较长观测系列)和G-Ⅱ组(13个较短观测系列).首先对各台站每分钟原始观测数据实施仔细修正,消除由地震和电脉冲等导致的错误数据和大气变化等干扰影响,再扣除理论潮汐重力信号获得观测残差.然后分别对各残差系列做Fourier谱分析,最后基于多台站资料迭积技术,求得亚潮汐频段上的积谱密度估计.在进一步消去剩余气压效应后,检测到8个公共谱峰.计算了这些谱峰的本征周期、品质因子和共振强度.数值结果说明其中3个公共谱峰的本征周期与Smith理论值间的最大差异小于1.0%,这种一致性说明了利用高精度地表重力观测可检测到固态内核的动力学现象.还检验了数值计算的可靠性,对地球自转和椭率可能导致的谱峰分裂现象进行了简要的探讨.
Based on the global distribution of 21 high-precision tidal gravity observations (about 86 years) from GWR superconducting gravimeters of 14 stations in the world, the translational oscillations of the Earth’s solid core were examined. The observations were divided into G-Ⅰ group Observation series) and G-II group (13 short observation series) .Firstly, every minute raw observation data of each station was carefully amended to eliminate the influence of the disturbance data such as earthquakes and electric pulses and atmospheric changes And deducted the theoretical tidal gravity signal to obtain the observed residuals .Furthermore, the Fourier spectrum analysis of each residual series was done, and finally the product spectral density estimation in the sub-tidal bands was obtained based on the multi-station data stacking technique.When the residual atmospheric pressure effect Eight common peaks were detected and the eigenvalues, quality factors and resonance intensities of these peaks were calculated.The numerical results show that the maximum difference between the eigenvalues of three common peaks and the Smith theoretical value is less than 1.0% , Which shows the dynamics of the solid core that can be detected using high-precision surface gravimetric observations, the reliability of numerical calculations, and the possible peak splitting caused by the Earth’s rotation and ellipticity A brief discussion of the line.