Justin Leung

Justin Leung


I am working with Dr. Andrew Walker and Dr. Paula Koelemeijer to better understand the physical properties of the lowermost mantle. I am particularly interested in the structure, composition, and origin of large low-wave velocity provinces (LLVPs). They are two continental-sized structures in the lowermost mantle of lower seismic wave velocities relative to their surroundings that cover 25 % of the core surface and rise 100s of km above the core-mantle boundary. 

There is still no consensus on the physical properties of LLVPs (e.g. density, structure, composition), which can be used to constrain possible hypotheses of their origin. These include chemically-distinct dense reservoirs or hot regions with concentrated mantle plumes that potentially feed material to surface volcanic hotspots. Hence, a better understanding of LLVPs can provide insight into unanswered questions of several planetary-scale processes, including mantle convection, thermal evolution of the planet, and mixing of chemical heterogeneity in the Earth’s interior.

I aim to obtain a better understanding of LLVPs using an interdisciplinary approach, integrating knowledge from seismology, geodynamics and mineral physics. I will be using a Bayesian approach to create synthetic Earth models, and determine the optimal model that best agrees with various forms of geophysical data. I am co-funded by the Oxford-NERC Environmental Research DTP and the Radcliffe Scholarship from University College.

I completed my undergraduate (integrated master’s degree) in Earth Sciences at Oxford. For my master’s project, I explored seismic anisotropic signatures at the Whillans Ice Stream to provide insights into its past and future deformation.