Array analyses of SmKS waves and the stratification of Earth's outermost core

研究成果: ジャーナルへの寄稿記事

11 引用 (Scopus)

抄録

We perform array analyses of SmKS waves in order to investigate the Vp structure of the Earth's outermost core. For earthquakes recorded by broadband seismometer networks in the world, we measure differential travel times between S3KS and S2KS, between S4KS and S3KS, and between S5KS and S3KS by array techniques. The differential times are well fit by a Vp model of the Earth's outermost core, KHOMC (Kaneshima and Helffrich, 2013). Differential slownesses of S4KS and S2KS relative to S2KS are also measured for the highest quality data. The measured slownesses, with unique sensitivity to the outer core 200–400 km below the CMB, are matched by KHOMC. These observations consolidate the evidence for the presence at the top of the outer core of a layer that has a distinctively steeper Vp gradient than the bulk of the outer core. We invert new SmKS differential time data set by a tau-p method and attempt to refine the Vp profile of KHOMC. The essential features of KHOMC are preserved after the model refinement. However, the newly estimated layer thickness is nearly 450 km, which is thicker than that of KHOMC. The Vp anomalies relative to PREM for the depths 400–800 km below the CMB are less than 0.03 km/s, consistent with the degree of agreement between different Vp models for the depth range.

元の言語英語
ページ(範囲)234-246
ページ数13
ジャーナルPhysics of the Earth and Planetary Interiors
276
DOI
出版物ステータス出版済み - 3 1 2018

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Earth core
outer core
stratification
seismographs
seismograph
data quality
travel time
travel
earthquakes
anomalies
broadband
anomaly
earthquake
gradients
sensitivity
profiles

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Geophysics
  • Physics and Astronomy (miscellaneous)
  • Space and Planetary Science

これを引用

Array analyses of SmKS waves and the stratification of Earth's outermost core. / Kaneshima, Satoshi.

:: Physics of the Earth and Planetary Interiors, 巻 276, 01.03.2018, p. 234-246.

研究成果: ジャーナルへの寄稿記事

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