29 June 2012 – Seminar
When: 4pm on Friday, 29th June 2012
Where: DIAS, Geophysics Section, 5 Merrion Square, Dublin 2, (library)
Speaker: Meghan S. Miller (University of Southern California)
Title: Segmented slabs beneath the central Mediterranean
Abstract:
To advance our understanding of the complex and episodic tectonic history of the central Mediterranean, we image the characteristics and structure of the convergent African and Eurasian lithospheric plates using S receiver functions. Specifically we investigate the lithospheric structure in terms of seismic velocity discontinuities, including the crust-mantle boundary (Moho) and the lithosphere-asthenosphere boundary (LAB) beneath Italy. The geometry and continuity of these structures are explored using teleseismic S-to-P converted phases, applied extensively throughout this region for the first time. Beneath the Northern Apennines and Calabria, where subduction is still active, we find evidence for a complex lithospheric structure, where two different negative S-velocity jumps are present at approximately 90 and 180 km depth. The shallowest negative phases are interpreted as the base of the lithosphere, but the second negative phases are much deeper than expected for the overriding plate lithosphere. When compared to hypocenter locations and p-wave tomography these deep converted phases correlate with the base of fast velocities perturbations in the upper mantle and regions with subcrustal earthquakes. These observations suggest that these deepest negative phases correspond to the base of the actively subducting lithosphere beneath the Northern Apennines and Calabria, and where these phases are absent in the receiver functions there is no subducting slab. Seismic imaging of the lithosphere and uppermost mantle using S-to-p conversions provides another geophysical dataset to aid in interpretation of the complex, segmented slab structure beneath Italy.
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Last Updated: 22nd March 2016 by Anna
2012-06-29 – Seminar: Meghan S. Miller
29 June 2012 – Seminar
When: 4pm on Friday, 29th June 2012
Where: DIAS, Geophysics Section, 5 Merrion Square, Dublin 2, (library)
Speaker: Meghan S. Miller (University of Southern California)
Title: Segmented slabs beneath the central Mediterranean
Abstract:
To advance our understanding of the complex and episodic tectonic history of the central Mediterranean, we image the characteristics and structure of the convergent African and Eurasian lithospheric plates using S receiver functions. Specifically we investigate the lithospheric structure in terms of seismic velocity discontinuities, including the crust-mantle boundary (Moho) and the lithosphere-asthenosphere boundary (LAB) beneath Italy. The geometry and continuity of these structures are explored using teleseismic S-to-P converted phases, applied extensively throughout this region for the first time. Beneath the Northern Apennines and Calabria, where subduction is still active, we find evidence for a complex lithospheric structure, where two different negative S-velocity jumps are present at approximately 90 and 180 km depth. The shallowest negative phases are interpreted as the base of the lithosphere, but the second negative phases are much deeper than expected for the overriding plate lithosphere. When compared to hypocenter locations and p-wave tomography these deep converted phases correlate with the base of fast velocities perturbations in the upper mantle and regions with subcrustal earthquakes. These observations suggest that these deepest negative phases correspond to the base of the actively subducting lithosphere beneath the Northern Apennines and Calabria, and where these phases are absent in the receiver functions there is no subducting slab. Seismic imaging of the lithosphere and uppermost mantle using S-to-p conversions provides another geophysical dataset to aid in interpretation of the complex, segmented slab structure beneath Italy.
Category: Geophysics Section News & Events
Happy Birthday! twitter.com/thecelticist/s…
The papers were 1) Affine Field Theory: conservation identitites and relation to Weyl and Eddington 2)The Union of the three fundamental fields (Gravitation, Menson, Electromagnetism) Which went on to secure worldwide acclaim. #DIASdiscovers
Date: 01 December 1943 Paper: The Irish Press Headline: Two Papers by Dr. Schroedinger Synopsis: 1943 was a busy year for Schroedinger. Not only did he deliver the "What is Life?" Lectures in @tcddublin in February in November he delivered two papers in the @RIAdawson (1/2)
Available to buy on the DIAS bookshop: books.dias.ie/index.php?main… (5/5) #DIASdiscovers #celtic #studies #twopatricks
"In the lives of St. Patrick, the two saints are invariably fused into one", said Prof. O'Rahilly in his lecture. The lecture was a condensation from O’Rahilly’s book “The two Patricks: a lecture on the history of Christianity in fifth-century Ireland”. (4/5)
He was known by his first name Patricius, which in later times would lead to confusion as he was succeeded by another apostle of the same name (Saint Patrick or Patricius in Latin). (3/5)
He spoke on "Palladius and Patrick". Palladius was the first bishop of the Christians of Ireland. (2/5)
Date: 21st March 1942 Paper: The Irish Press Headline: Palladius and Patrick | School Of Celtic Studies Lecture Synopsis: The first public lecture under the auspices of the School of Celtic Studies was delivered in Trinity College by Professor T. F. O'Rahilly in 1942. (1/5)
As part of our ongoing participation in the @HistFest we decided to take a look into the Irish Newspaper Archives and see where DIAS made it into print over the last 80 years. There were so many articles, the hardest part was selecting what we would post. We hope you enjoy!
@AReillyFailte @CultureNight @VisitDublin Thanks Antoinette! Glad you enjoyed 😊
Big thank you to @MartinaPQuinn of @helloalicepr for moderating the discussion, and of course to our panel @NeasaMcG @CormacORafferty and @laoneill111
@CormacORafferty "to cut yourself off from fundamental research means you could miss out on some of the biggest ideas"
@laoneill "it's our job as researchers to keep reminding governments how important basic research is" "For Dev basic research being carried out in Ireland was a badge of pride"
@NeasaMcG Schrödinger's work in causality was not well received by the religious authorities at the time At the same time DIAS did have Catholic priests working on research projects in the early days, so there was not the conflict you might think between science and religion
@laoneill111 Schrödinger was very popular in social circles in Dublin, a bit of a renaissance man
@CormacORafferty Schrödinger was gifted at explaining difficult concepts
@CormacORafferty on how unsuccessful work, in Schrödinger's case, unified field theory, is just as important part of science. And no one has managed to crack it yet! And not forgetting the cat
@laoneill111 how Schrödinger's book inspired scientists to change fields and result in the finding of the double helix.