Listening to the Whispers of the Earth
École Normale Supérieure
https://cnrs.zoom.us/j/94454044370?pwd=cjI0U1hIN1BsOXVrK0RxVHU5dUFMUT09 Abstract: What can the Earth tell us about itself? Over the past two decades, seismic interferometry has spawned the reconstruction of continuous empirical Green’s functions using continuous seismic noise and made it feasible to continuously and non-destructively monitor subsurface structures from the very subsurface down to the lower crust of the Earth. Because of the relationship between seismic wave velocity and shear modulus, seismic waves carry information on the long-term and transient deformation of subsurface medium under combined effects of multiple forces from tectonic and local environmental factors, such as the rainfall, snow, sea level changes, etc. I will introduce some background and theories behind ambient seismic noise and seismic interferometry. The emphasis will be put on some comprehensive applications to disclose the spatial-temporal evolution of the Earth’s medium from local to regional scales by tracking the seismic velocity changes through listening to the Earth’s whispers.