1. We perform a global survey of the 520- and 560-km mantle discontinuity by
analyzing SS precursors.
2. Our observations confirm the global existence of the 520-km discontinuity.
3. Depth variations of the 520-km discontinuity correlate with the mid-MTZ temperature.
4. Compositional heterogeneity also contributes to the 520-km discontinuity topography.
5. A 560-km discontinuity is sporadically detected in subduction zones and mantle upwells.
6. The existence of the 560-km discontinuity may imply localized Ca-enrichment
in the mid-MTZ possibly related to the recycling of oceanic crust.
The Generic Mapping Tools (GMT) software is ubiquitous in the Earth and ocean sciences.
As a cross‐platform tool producing high‐quality maps and figures, it is used by tens of
thousands of scientists around the world. The basic syntax of GMT scripts …
We discuss the question whether inner core (IC) differential rotation or
temporal change of the IC surface provides a consistent interpretation
for temporal changes of the IC‐related phases and their coda. While temporal
change of the IC surface is …
Deep earthquakes exhibit strong variabilities in their rupture and aftershock
characteristics, yet their physical failure mechanisms remain elusive.
The 2018 Mw 8.2 and Mw 7.9 Tonga-Fiji deep earthquakes, the two largest ever
recorded in this …
By using an on-site collapse event as a reference and eliminating path effects
of seismic-wave propagation, we constrain source characteristics of
North Korea's 3 September 2017 nuclear test.
In the framework of a complete source model for an …
The 3 September 2017 nuclear test conducted by the Democratic People's Republic
of Korea was followed by a series of small seismic events. In this study,
we conduct a survey of small seismic events from 1 May 2017 to 25 April 2018
near North Korea's …
1. We present high-precision locations and detailed source information of
four small seismic events following North Korea's 2017 nuclear test.
2. The first event is an on-site collapse 440 m northwest of the test site
and best explained by a near vertical single force.
3. The later events are an earthquake swarm located 8.4 km north of the test
site with a focal depth of at least 2.4 km.
Modern seismology has revealed complex structures of the Earth's inner core and its boundary.
The interior of the Earth’s inner core exhibits both velocity and attenuation anisotropy,
and hemispherical variations of velocity, attenuation and …
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 …