BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Mantle seismic imaging from top to bottom: subduction dynamics\, t
 ransition zone topography and core-mantle boundary anisotropy - Florian Mi
 llet (University of Cambridge)
DTSTART:20210120T160000Z
DTEND:20210120T170000Z
UID:TALK155329@talks.cam.ac.uk
CONTACT:Sam Wimpenny
DESCRIPTION:Seismic waves generated at moderate to large earthquakes trave
 l through the entire Earth as compressional (P) or shear (S) disturbances 
 and are recorded at seismic stations across the globe. When these seismic 
 waves interact with strong heterogeneities or discontinuities in the Earth
 's structure\, they can be converted\, split and diffracted along or acros
 s the boundaries of these structures. Here I will be looking at a couple m
 ethods we can use to extract information from the ever-growing seismic dat
 abases to learn more about the Earth's mantle using these complex seismic 
 phases. First\, I will present a novel receiver-side diffracted waves (rec
 eiver functions) imaging method that allows to get high resolution 3D imag
 es of the lithosphere and upper mantle at continental scales under dense s
 eismic deployments. This imaging technique is applied to subduction zone s
 ettings\, in particular under southern Alaska\, where it reveals the fine 
 structure of the transition from oceanic plateau to regular Pacific lithos
 phere subduction at depth. Then I will discuss ongoing plans to adapt this
  method to the deep Earth\, with a particular focus on the mantle transiti
 on zone and its complex topography. I will show preliminary results for a 
 large composite array under Greece and Turkey. Finally\, I will discuss so
 me ideas about a potential new methodology to automatically search for sui
 table source-receiver geometries to study the anisotropy within the deepes
 t parts of the mantle\, at the limit between the regular / faster mantle a
 nd the large low velocity provinces (LLVP) under Africa and the Pacific at
  the core-mantle boundary.
LOCATION:ONLINE - Details to be sent by email
END:VEVENT
END:VCALENDAR