Mineral Physics of Earth and Planetary Interiors
With the rapid advances of the past decade in ultrahigh-pressure x-ray synchrotron technology, researchers are now able to tackle some of the most fundamental, long-standing questions regarding Earth and planetary interiors. What is the origin of seismic anisotropy in the inner core? What is the source of the enigmatic seismic features at the core-mantle boundary? How did the core and mantle differentiate in the early Earth?
SLAC highlight of our work at the MEC beamline with our multi-institutional team
Planetary Core Formation
Early-stage core-mantle differentiation and core formation represent pivotal geological events that defined the major geochemical and geophysical signatures of Earth. In order to test potential mechanisms and hypotheses of core formation, we need textural information on the interaction and separation of the solid and liquid phases.
Earth’s D” Layer
The D” layer, the lowermost portion of the mantle, sits just above the molten iron-rich outer core. Seismic observations have revealed a region with an intriguingly complex signature. This relatively thin layer, varying around 250 km in thickness, may hold the key to understanding how the core and mantle interact. The D” layer may also be where deep mantle plumes originate and where subducting slabs terminate. Some of the most puzzling seismic features include the splitting of shear-waves travelling through this layer and the presence of ultralow-velocity zones (ULVZ).
Inner core anisotropy
Located over 5000 km below the Earth’s surface, the inner core represents the most remote portion of our planet.