Carissimi Associati SGI,
Carissimi Soci Società Associate,
su indicazione del Prof. Rodolfo Carosi (Università di Torino e Presidente SGI) vi segnaliamo l'ultimo podcast di Geology Bites (Conversations about geology with researchers making key contributions to our understanding of the Earth and the Solar System):
Andreas Fichtner (Professor at the Federal Institute of Technology, Zurich) on the Frontiers of Seismic Imaging.
Di seguito troverete il messaggio dell'ideatore, Oliver Strimpel, e il link al sito web di Geology Bites.
Cordiali saluti,
La Segreteria
Hello, listeners,
This episode is about seismic tomography. It's not the first time I've addressed this topic, but I felt that exciting things were happening in the field and I wanted to know about the latest developments.
When you listen to Andreas Fichtner, you learn how the entire field is vitiated by the non-uniqueness of the solutions and the sparsity of data. Yet he was able to reassure us that no matter what arbitrary decisions you make and how you fill in what's missing, some structures emerge clearly in all the models. One of these is the plume under Iceland, which can be traced all the way down to the core-mantle boundary. Of course, that immediately raises the question of whether we'll see in a robust fashion all the other plumes that have been posited by researchers over the years when our tomographic images get sharper.
Towards the end of the episode he tells us about sensing seismic data using fiber-optic cables — both existing telecommunication cables and new ones installed for the purpose. Such methods can yield an order of magnitude in improved spatial resolution. So far most fiber-optic studies have not been used to do tomographic imaging so much as to map microquakes near volcanoes or in ice flows or to assess earthquake hazard in cities. However, I have included one fiber-optic tomographic study of an active caldera in California on the episode web page.
Fichtner a Professor in the Department of Earth and Planetary Sciences at the Federal Institute of Technology in Zurich.
I hope you enjoy listening,
Oliver