Speaker: Mengfei Qi
Affiliation: EPSS, UCLA
Date: Wednesday, May 27, 2026
Time: 12:00 PM
Abstract
The Pacific Ocean covers a large portion of the Earth’s surface. However, seismic constraints on its crust and upper mantle structure remain limited due to sparse station coverage. Ambient noise tomography provides an effective approach to improving spatial coverage by extracting empirical Green’s functions (EGFs) between station pairs, while also offering enhanced vertical constraints on crustal structure. In this study, I use continuous seismic data from both land-based stations and ocean-bottom seismometers (OBS) to measure Rayleigh wave group and phase velocity dispersion across the Pacific region, targeting the period 1990–2025. Preliminary results based on the 2005–2006 datasets demonstrate that reliable dispersion curves can be obtained for station pairs at appropriate interstation distances over a period range of 5–50 s. Ongoing work focuses on incorporating additional years of data and improving signal quality, particularly for OBS records, to enhance path coverage and support future tomographic imaging of oceanic structure.