Signature of 3-D density structure in spectra of the spheroidal free oscillation 0S2
Signature of 3-D density structure in spectra of the spheroidal free oscillation 0S2
复制标题
DOI：
10.1093/gji/ggs013
复制
发表时间：
2013-04
影响因子：
2.8
通讯作者：
R. Häfner;R. Widmer-Schnidrig
中科院分区：
文献类型：
--
作者：
R. Häfner;R. Widmer-Schnidrig
重力仪记录的三个最近的特大逆冲断层地震被用来调查分裂的基本椭球模式0 S2。受益于最近的改进超导重力仪的设计和性能，并使用多锥度的频谱分析，我们得到的单线态频率更小，更强大的误差比以前的研究。基于正演模拟实验，我们可以表明，单重态频率的误差是足够小，使物理上合理的3-D密度模型之间的歧视。本文给出了旋转分裂参数θ S2的一个估计，它对球对称质量密度分布提供了一个线性积分约束，这与地球质量或地球转动惯量的约束很相似，而且它的相对误差小于地球质量的相对误差。
Gravimeter records of three recent megathrust earthquakes are used to investigate the splitting of the fundamental spheroidal mode0S2. Benefiting from recent improvements in the design and performance of superconducting gravimeters and using multitapers for the spectral analysis we obtain singlet frequencies with smaller and more robust error bars than previous studies. Based on forward modelling experiments we can show that the errors of the singlet frequencies are small enough to enable discrimination between physically plausible 3-D density models. We present an estimate of the rotational splitting parameter of0S2, which provides a linear integral constraint on the spherically symmetric mass density distribution much like the Earth's mass or the Earth's moment of inertia do and whose relative error is smaller than that of the Earth's mass.