Wednesday, April 2

Smith Lecture Friday April 4

Dear All,
Our Smith Lecture speaker this week is  Andy Nyblade, Penn State.  He is speaking on Cenozoic Extension, Volcanism and Plateau Uplift in Eastern Africa and the African Superplume.  Abstract below.

Smith Lectures are Friday afternoons from 4:00 to 5:00 pm, in Room 1528 C.C. Little Building.  A reception is held following the lecture in 2540 C.C. Little. The events are free and open to the public.  A full schedule for the term may be found on our website:
http://www.lsa.umich.edu/earth/events/

Note there is no lecture April 11; the next lecture is Friday April 18.


Best regards, -Anne
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Anne Hudon
Academic Student Services
Department of Earth and Environmental Sciences
University of Michigan
http://www.lsa.umich.edu/earth/
  
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Abstract:
The African superplume is arguably the largest feature in Earth’s lower mantle and whether or not it extends into the upper mantle beneath eastern Africa, giving rise to the Cenozoic rifting, volcanism and plateau uplift found there, has long been debated.  New seismic images of mantle structure obtained from modeling AfricaArray data indicate that the superplume is indeed a whole-mantle structure.  The images come from body and surface wave tomography, receiver function stacks illuminating topography on the 410 and 660 km discontinuities, and shear wave splitting.   The seismic images are consistent with a thermal anomaly of a few hundred degrees spanning the mid-mantle connecting anomalous lower mantle structure under southern Africa with anomalous upper mantle structure under eastern Africa.