FISH Seminar: Florent Brenguier (Univ. Grenoble Alpes)
Virtual seismic source monitoring of Earthquakes
The early work of Aki 1957 paved the way to the use of erratic, seismic noise as an ubiquitous source of useful signal for imaging the Earth. More recently, in the last 15 years, theoretical, numerical, laboratory and seismological data studies have proved our ability to reconstruct virtual seismic sources at a seismic receiver location by simply cross-correlating continuous records of ambient seismic noise at different seismometers. This major advance has revolutionized our ability to image the Earth. This presentation will show how virtual seismic sources can be used for monitoring the instantaneous and post-seismic response of the crust to large earthquakes. We will in particular cover the 2004 Parkfield and 2011 Tohoku-Oki earthquakes and show some intriguing observations of high sensitivity of crustal seismic velocities to earthquake shacking that we interpret as the response of the highly fluid pressurized upper crust.
About the Series
The Friday Informal Seminar Hour [FISH, Earth Resources Laboratory] is a postdoc-run weekly seminar series within the ERL. Topics include research relating to geophysics, and in particular seismology, with applications in Earth resources exploration such as e.g. seismics exploration, microseismicity, earthquake physics, and Earth imaging techniques. The seminars usually take place on Fridays at 12 noon in 54-209 (term-time only).