Dr Yuan is an observational seismologist, and specializes in continental lithospheric structural imaging using earthquake seismology. His current research focuses on: continent formation and modification tectonics; array seismology; multiple scale isotropic and anisotropic mantle velocity structure; crustal and upper mantle structural imaging; P- and S-wave travel-time tomography; surface waveform tomography; P- and S-wave receiver functions; Shear wave splitting; ambient noise tomography; Spectral element and adjoint waveform tomography in regional and global inversions.