Recent News

  • Dec. 2017: Dongdong Tian is awarded the 2017 CGU Outstanding Student Paper Award for his presentation at the 2017 CGU annual meeting.
  • Oct. 2017: Dongdong Tian is awarded the National Scholarship for Doctoral Students from the Ministry of Education, China.


Inner Core Boundary

Use pre-critically reflected PKiKP waves to study the fine-scale structure of the Earth’s inner core boundary.

Selected Publications

Although existence of a mushy zone in the Earth’s inner core has been hypothesized several decades ago, no seismic evidence has ever been reported. Based on waveform modeling of seismic compressional waves that are reflected off the Earth’s inner core boundary, here we present seismic evidence for a localized 4–8 km thick zone across the inner core boundary beneath southwest Okhotsk Sea with seismic properties intermediate between those of the inner and outer core and of a mushy zone. Such a localized mushy zone is found to be surrounded by a sharp inner core boundary nearby. These seismic results suggest that, in the current thermo-compositional state of the Earth’s core, the outer core composition is close to eutectic in most regions resulting in a sharp inner core boundary, but deviation from the eutectic composition exists in some localized regions resulting in a mushy zone with a thickness of 4–8 km.
Nature Communications,2017


. Seismic structure and dynamic process of the Earth's inner core and its boundary. Chinese Journal of Geophysics (in Chinese), 2018.


. Microseismic sources during Hurricane Sandy. Journal of Geophysical Research: Solid Earth, 2015.


. A new method for earthquake depth determination: stacking multiple-station autocorrelograms. Geophysical Journal International, 2014.


Recent & Upcoming Talks

Seismological evidence for a localized mushy zone at the Earth's inner core boundary
Oct 17, 2017 1:50 PM
Getting started with GMT in 60 minutes
Sep 21, 2016 9:00 AM


Softwares &
Documentations &


  • HinetPy: A python package to request and process seismic waveform data from Hi-net.