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IRIS WEBINAR: Tomographic Study of Lithosphere Dynamics in the Eastern Mediterranean - 3/12, 2 PM Eastern
From: Andy Frassetto <andyf@xxxxxxxx>IRIS WEBINAR: Tomographic Study of Lithosphere Dynamics in the Eastern Mediterranean - 3/12, 2 PM Eastern
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"A Snapshot of Eastern Mediterranean Lithosphere and Upper Mantle: Clues for the Demise of Tethys Ocean" will be presented at 2 pm EST (6 pm UTC) on Wednesday, 3/12.
Please register *only* if you intend to watch the webinar live: https://www2.gotomeeting.com/register/857750082
You will be emailed a confirmation containing a link for watching the live broadcast. A recording will be subsequently posted here: http://www.youtube.com/user/IRISEnO. Access to older webinars, along with related materials and information is found here: http://www.iris.edu/hq/webinar/
Presenter: Dr. C. Berk Biryol, Postdoctoral Research Associate, University of North Carolina at Chapel Hill
Abstract: The tectonics of the Mediterranean region is characterized by an intricate configuration of arcuate subduction zones and mountain belts. The evolution and the geodynamics of these zones are controlled by closure of Tethys Ocean between converging Eurasia and Africa. The interplay between convergence-related compression and slab rollback related extension is further complicated by processes such as termination of subduction, tearing and detachment of subducting oceanic lithosphere. Our recent studies using various seismological techniques reveal the complexity of lithospheric and upper mantle structures in the Anatolian region using a dataset composed of over 200 seismic stations.
Our body-wave tomography results reveal segmented layout of the Aegean and the Cyprus slabs that are separated from each other by a tear as wide as 300 km beneath Western Anatolia. The geometry of this tear suggests it was formed by differential subduction and rollback rates along the Aegean and Cyprus trenches. This configuration of slabs and the associated geodynamic setting is consistent with our upper mantle seismic anisotropy observations from shear-wave splitting measurements favoring a SW direction of asthenospheric flow. We infer that this flow is controlled by the differential forces acting on the upper-mantle, exerted by the slab-roll-back taking place along the Aegean and the Cyprean Subduction Zones. The gaps associated with the slab tears and edges are occupied by slow velocity material and underlie major volcanic provinces of Anatolia. Recent ambient noise tomography results reveal the fragmented nature of the Anatolian lithosphere with seismic velocity variations across paleo-suture zones and major active-tectonic features such as the North Anatolian Fault Zone.
Overall, our observations hold important clues about the effects of Tethys Ocean closure on the structure of subduction zones and lithosphere in the eastern Mediterranean.
Please direct any related questions or the name of your favorite seismic station to Andy Frassetto (andyf@xxxxxxxx).
System Requirements
PC-based attendees: Windows® 8, 7, Vista, XP or 2003 Server
Mac®-based attendees: Mac OS® X 10.6 or newer
Mobile attendees: iPhone®, iPad®, Android™ phone or Android tablet
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