Paper No. 4
Presentation Time: 8:45 AM


WYSESSION, Michael, Earth and Planetary Sciences, Washington University, Campus Box 1169, 1 Brookings Dr, St. Louis, MO 63130,

We present results for the seismic structure beneath Madagascar, Mozambique, and the surrounding regions from several different seismic studies using data from the recent NSF-funded MACOMO IRIS PASSCAL broadband seismic deployment. A total of 32 seismometers were deployed in Madagascar and Mozambique during 2011-2013, providing unprecedented seismic resolution of the subsurface structure using receiver functions, body wave tomography, seismic noise tomography, and two-plane-wave surface wave tomography. Half of the stations were deployed in 2011, with the second half deployed in 2012. All stations were removed in 2013. Madagascar is unusual in that it has experienced intraplate volcanism in the middle and northern parts of the island. Several hypotheses can explain this, including mantle flow associated with the Reunion hotspot, flow associated with the African Rifting, continental edge convection, or a mantle plume associated with the lowermost mantle large low shear velocity province (LLSVP) at the core-mantle boundary. The combination of the different seismic techniques allow for these hypotheses to be tested.
  • Wysession_GSA_Madagascar.pdf (42.5 MB)