Inner Core Differential Motion Confirmed by Earthquake Waveform Doublets

@article{Zhang2005InnerCD,
  title={Inner Core Differential Motion Confirmed by Earthquake Waveform Doublets},
  author={Jian Zhang and Xiaodong Song and Yingchun Li and Paul G. Richards and Xinlei Sun and Felix Waldhauser},
  journal={Science},
  year={2005},
  volume={309},
  pages={1357 - 1360}
}
We analyzed 18 high-quality waveform doublets with time separations of up to 35 years in the South Sandwich Islands region, for which the seismic signals have traversed the inner core as PKP(DF). The doublets show a consistent temporal change of travel times at up to 58 stations in and near Alaska, and they show a dissimilarity of PKP(DF) coda. Using waveform doublets avoids artifacts of earthquake mislocations and contamination from small-scale heterogeneities. Our results confirm that Earth's… 

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